CINXE.COM

Area - Wikipedia

<!DOCTYPE html> <html class="client-nojs vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-sticky-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-enabled skin-theme-clientpref-day vector-toc-available" lang="en" dir="ltr"> <head> <meta charset="UTF-8"> <title>Area - Wikipedia</title> <script>(function(){var className="client-js vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-sticky-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-enabled skin-theme-clientpref-day vector-toc-available";var cookie=document.cookie.match(/(?:^|; )enwikimwclientpreferences=([^;]+)/);if(cookie){cookie[1].split('%2C').forEach(function(pref){className=className.replace(new RegExp('(^| )'+pref.replace(/-clientpref-\w+$|[^\w-]+/g,'')+'-clientpref-\\w+( |$)'),'$1'+pref+'$2');});}document.documentElement.className=className;}());RLCONF={"wgBreakFrames":false,"wgSeparatorTransformTable":["",""],"wgDigitTransformTable":["",""],"wgDefaultDateFormat":"dmy", "wgMonthNames":["","January","February","March","April","May","June","July","August","September","October","November","December"],"wgRequestId":"ccdf68ac-1dca-4568-9588-3284187e7445","wgCanonicalNamespace":"","wgCanonicalSpecialPageName":false,"wgNamespaceNumber":0,"wgPageName":"Area","wgTitle":"Area","wgCurRevisionId":1255146594,"wgRevisionId":1255146594,"wgArticleId":1209,"wgIsArticle":true,"wgIsRedirect":false,"wgAction":"view","wgUserName":null,"wgUserGroups":["*"],"wgCategories":["CS1: long volume value","Articles with short description","Short description is different from Wikidata","Wikipedia indefinitely move-protected pages","Articles with excerpts","Pages using Sister project links with hidden wikidata","Pages using Sister project links with default search","Area"],"wgPageViewLanguage":"en","wgPageContentLanguage":"en","wgPageContentModel":"wikitext","wgRelevantPageName":"Area","wgRelevantArticleId":1209,"wgIsProbablyEditable":true,"wgRelevantPageIsProbablyEditable":true, "wgRestrictionEdit":[],"wgRestrictionMove":["sysop"],"wgRedirectedFrom":"Areas","wgNoticeProject":"wikipedia","wgCiteReferencePreviewsActive":false,"wgFlaggedRevsParams":{"tags":{"status":{"levels":1}}},"wgMediaViewerOnClick":true,"wgMediaViewerEnabledByDefault":true,"wgPopupsFlags":0,"wgVisualEditor":{"pageLanguageCode":"en","pageLanguageDir":"ltr","pageVariantFallbacks":"en"},"wgMFDisplayWikibaseDescriptions":{"search":true,"watchlist":true,"tagline":false,"nearby":true},"wgWMESchemaEditAttemptStepOversample":false,"wgWMEPageLength":40000,"wgInternalRedirectTargetUrl":"/wiki/Area","wgRelatedArticlesCompat":[],"wgCentralAuthMobileDomain":false,"wgEditSubmitButtonLabelPublish":true,"wgULSPosition":"interlanguage","wgULSisCompactLinksEnabled":false,"wgVector2022LanguageInHeader":true,"wgULSisLanguageSelectorEmpty":false,"wgWikibaseItemId":"Q11500","wgCheckUserClientHintsHeadersJsApi":["brands","architecture","bitness","fullVersionList","mobile","model","platform","platformVersion"], "GEHomepageSuggestedEditsEnableTopics":true,"wgGETopicsMatchModeEnabled":false,"wgGEStructuredTaskRejectionReasonTextInputEnabled":false,"wgGELevelingUpEnabledForUser":false};RLSTATE={"ext.globalCssJs.user.styles":"ready","site.styles":"ready","user.styles":"ready","ext.globalCssJs.user":"ready","user":"ready","user.options":"loading","ext.math.styles":"ready","ext.cite.styles":"ready","skins.vector.search.codex.styles":"ready","skins.vector.styles":"ready","skins.vector.icons":"ready","jquery.makeCollapsible.styles":"ready","ext.wikimediamessages.styles":"ready","ext.visualEditor.desktopArticleTarget.noscript":"ready","ext.uls.interlanguage":"ready","wikibase.client.init":"ready","ext.wikimediaBadges":"ready"};RLPAGEMODULES=["mediawiki.action.view.redirect","ext.cite.ux-enhancements","mediawiki.page.media","site","mediawiki.page.ready","jquery.makeCollapsible","mediawiki.toc","skins.vector.js","ext.centralNotice.geoIP","ext.centralNotice.startUp","ext.gadget.ReferenceTooltips", "ext.gadget.switcher","ext.urlShortener.toolbar","ext.centralauth.centralautologin","mmv.bootstrap","ext.popups","ext.visualEditor.desktopArticleTarget.init","ext.visualEditor.targetLoader","ext.echo.centralauth","ext.eventLogging","ext.wikimediaEvents","ext.navigationTiming","ext.uls.interface","ext.cx.eventlogging.campaigns","ext.cx.uls.quick.actions","wikibase.client.vector-2022","ext.checkUser.clientHints","ext.growthExperiments.SuggestedEditSession","wikibase.sidebar.tracking"];</script> <script>(RLQ=window.RLQ||[]).push(function(){mw.loader.impl(function(){return["user.options@12s5i",function($,jQuery,require,module){mw.user.tokens.set({"patrolToken":"+\\","watchToken":"+\\","csrfToken":"+\\"}); }];});});</script> <link rel="stylesheet" href="/w/load.php?lang=en&amp;modules=ext.cite.styles%7Cext.math.styles%7Cext.uls.interlanguage%7Cext.visualEditor.desktopArticleTarget.noscript%7Cext.wikimediaBadges%7Cext.wikimediamessages.styles%7Cjquery.makeCollapsible.styles%7Cskins.vector.icons%2Cstyles%7Cskins.vector.search.codex.styles%7Cwikibase.client.init&amp;only=styles&amp;skin=vector-2022"> <script async="" src="/w/load.php?lang=en&amp;modules=startup&amp;only=scripts&amp;raw=1&amp;skin=vector-2022"></script> <meta name="ResourceLoaderDynamicStyles" content=""> <link rel="stylesheet" href="/w/load.php?lang=en&amp;modules=site.styles&amp;only=styles&amp;skin=vector-2022"> <meta name="generator" content="MediaWiki 1.44.0-wmf.4"> <meta name="referrer" content="origin"> <meta name="referrer" content="origin-when-cross-origin"> <meta name="robots" content="max-image-preview:standard"> <meta name="format-detection" content="telephone=no"> <meta property="og:image" content="https://upload.wikimedia.org/wikipedia/commons/thumb/a/a7/Squaring_the_circle.svg/1200px-Squaring_the_circle.svg.png"> <meta property="og:image:width" content="1200"> <meta property="og:image:height" content="1200"> <meta property="og:image" content="https://upload.wikimedia.org/wikipedia/commons/thumb/a/a7/Squaring_the_circle.svg/800px-Squaring_the_circle.svg.png"> <meta property="og:image:width" content="800"> <meta property="og:image:height" content="800"> <meta property="og:image" content="https://upload.wikimedia.org/wikipedia/commons/thumb/a/a7/Squaring_the_circle.svg/640px-Squaring_the_circle.svg.png"> <meta property="og:image:width" content="640"> <meta property="og:image:height" content="640"> <meta name="viewport" content="width=1120"> <meta property="og:title" content="Area - Wikipedia"> <meta property="og:type" content="website"> <link rel="preconnect" href="//upload.wikimedia.org"> <link rel="alternate" media="only screen and (max-width: 640px)" href="//en.m.wikipedia.org/wiki/Area"> <link rel="alternate" type="application/x-wiki" title="Edit this page" href="/w/index.php?title=Area&amp;action=edit"> <link rel="apple-touch-icon" href="/static/apple-touch/wikipedia.png"> <link rel="icon" href="/static/favicon/wikipedia.ico"> <link rel="search" type="application/opensearchdescription+xml" href="/w/rest.php/v1/search" title="Wikipedia (en)"> <link rel="EditURI" type="application/rsd+xml" href="//en.wikipedia.org/w/api.php?action=rsd"> <link rel="canonical" href="https://en.wikipedia.org/wiki/Area"> <link rel="license" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en"> <link rel="alternate" type="application/atom+xml" title="Wikipedia Atom feed" href="/w/index.php?title=Special:RecentChanges&amp;feed=atom"> <link rel="dns-prefetch" href="//meta.wikimedia.org" /> <link rel="dns-prefetch" href="//login.wikimedia.org"> </head> <body class="skin--responsive skin-vector skin-vector-search-vue mediawiki ltr sitedir-ltr mw-hide-empty-elt ns-0 ns-subject mw-editable page-Area rootpage-Area skin-vector-2022 action-view"><a class="mw-jump-link" href="#bodyContent">Jump to content</a> <div class="vector-header-container"> <header class="vector-header mw-header"> <div class="vector-header-start"> <nav class="vector-main-menu-landmark" aria-label="Site"> <div id="vector-main-menu-dropdown" class="vector-dropdown vector-main-menu-dropdown vector-button-flush-left vector-button-flush-right" > <input type="checkbox" id="vector-main-menu-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-main-menu-dropdown" class="vector-dropdown-checkbox " aria-label="Main menu" > <label id="vector-main-menu-dropdown-label" for="vector-main-menu-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-menu mw-ui-icon-wikimedia-menu"></span> <span class="vector-dropdown-label-text">Main menu</span> </label> <div class="vector-dropdown-content"> <div id="vector-main-menu-unpinned-container" class="vector-unpinned-container"> <div id="vector-main-menu" class="vector-main-menu vector-pinnable-element"> <div class="vector-pinnable-header vector-main-menu-pinnable-header vector-pinnable-header-unpinned" data-feature-name="main-menu-pinned" data-pinnable-element-id="vector-main-menu" data-pinned-container-id="vector-main-menu-pinned-container" data-unpinned-container-id="vector-main-menu-unpinned-container" > <div class="vector-pinnable-header-label">Main menu</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-main-menu.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-main-menu.unpin">hide</button> </div> <div id="p-navigation" class="vector-menu mw-portlet mw-portlet-navigation" > <div class="vector-menu-heading"> Navigation </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-mainpage-description" class="mw-list-item"><a href="/wiki/Main_Page" title="Visit the main page [z]" accesskey="z"><span>Main page</span></a></li><li id="n-contents" class="mw-list-item"><a href="/wiki/Wikipedia:Contents" title="Guides to browsing Wikipedia"><span>Contents</span></a></li><li id="n-currentevents" class="mw-list-item"><a href="/wiki/Portal:Current_events" title="Articles related to current events"><span>Current events</span></a></li><li id="n-randompage" class="mw-list-item"><a href="/wiki/Special:Random" title="Visit a randomly selected article [x]" accesskey="x"><span>Random article</span></a></li><li id="n-aboutsite" class="mw-list-item"><a href="/wiki/Wikipedia:About" title="Learn about Wikipedia and how it works"><span>About Wikipedia</span></a></li><li id="n-contactpage" class="mw-list-item"><a href="//en.wikipedia.org/wiki/Wikipedia:Contact_us" title="How to contact Wikipedia"><span>Contact us</span></a></li> </ul> </div> </div> <div id="p-interaction" class="vector-menu mw-portlet mw-portlet-interaction" > <div class="vector-menu-heading"> Contribute </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-help" class="mw-list-item"><a href="/wiki/Help:Contents" title="Guidance on how to use and edit Wikipedia"><span>Help</span></a></li><li id="n-introduction" class="mw-list-item"><a href="/wiki/Help:Introduction" title="Learn how to edit Wikipedia"><span>Learn to edit</span></a></li><li id="n-portal" class="mw-list-item"><a href="/wiki/Wikipedia:Community_portal" title="The hub for editors"><span>Community portal</span></a></li><li id="n-recentchanges" class="mw-list-item"><a href="/wiki/Special:RecentChanges" title="A list of recent changes to Wikipedia [r]" accesskey="r"><span>Recent changes</span></a></li><li id="n-upload" class="mw-list-item"><a href="/wiki/Wikipedia:File_upload_wizard" title="Add images or other media for use on Wikipedia"><span>Upload file</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> <a href="/wiki/Main_Page" class="mw-logo"> <img class="mw-logo-icon" src="/static/images/icons/wikipedia.png" alt="" aria-hidden="true" height="50" width="50"> <span class="mw-logo-container skin-invert"> <img class="mw-logo-wordmark" alt="Wikipedia" src="/static/images/mobile/copyright/wikipedia-wordmark-en.svg" style="width: 7.5em; height: 1.125em;"> <img class="mw-logo-tagline" alt="The Free Encyclopedia" src="/static/images/mobile/copyright/wikipedia-tagline-en.svg" width="117" height="13" style="width: 7.3125em; height: 0.8125em;"> </span> </a> </div> <div class="vector-header-end"> <div id="p-search" role="search" class="vector-search-box-vue vector-search-box-collapses vector-search-box-show-thumbnail vector-search-box-auto-expand-width vector-search-box"> <a href="/wiki/Special:Search" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only search-toggle" title="Search Wikipedia [f]" accesskey="f"><span class="vector-icon mw-ui-icon-search mw-ui-icon-wikimedia-search"></span> <span>Search</span> </a> <div class="vector-typeahead-search-container"> <div class="cdx-typeahead-search cdx-typeahead-search--show-thumbnail cdx-typeahead-search--auto-expand-width"> <form action="/w/index.php" id="searchform" class="cdx-search-input cdx-search-input--has-end-button"> <div id="simpleSearch" class="cdx-search-input__input-wrapper" data-search-loc="header-moved"> <div class="cdx-text-input cdx-text-input--has-start-icon"> <input class="cdx-text-input__input" type="search" name="search" placeholder="Search Wikipedia" aria-label="Search Wikipedia" autocapitalize="sentences" title="Search Wikipedia [f]" accesskey="f" id="searchInput" > <span class="cdx-text-input__icon cdx-text-input__start-icon"></span> </div> <input type="hidden" name="title" value="Special:Search"> </div> <button class="cdx-button cdx-search-input__end-button">Search</button> </form> </div> </div> </div> <nav class="vector-user-links vector-user-links-wide" aria-label="Personal tools"> <div class="vector-user-links-main"> <div id="p-vector-user-menu-preferences" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-userpage" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <nav class="vector-appearance-landmark" aria-label="Appearance"> <div id="vector-appearance-dropdown" class="vector-dropdown " title="Change the appearance of the page&#039;s font size, width, and color" > <input type="checkbox" id="vector-appearance-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-appearance-dropdown" class="vector-dropdown-checkbox " aria-label="Appearance" > <label id="vector-appearance-dropdown-label" for="vector-appearance-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-appearance mw-ui-icon-wikimedia-appearance"></span> <span class="vector-dropdown-label-text">Appearance</span> </label> <div class="vector-dropdown-content"> <div id="vector-appearance-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <div id="p-vector-user-menu-notifications" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-overflow" class="vector-menu mw-portlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="https://donate.wikimedia.org/wiki/Special:FundraiserRedirector?utm_source=donate&amp;utm_medium=sidebar&amp;utm_campaign=C13_en.wikipedia.org&amp;uselang=en" class=""><span>Donate</span></a> </li> <li id="pt-createaccount-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Special:CreateAccount&amp;returnto=Area" title="You are encouraged to create an account and log in; however, it is not mandatory" class=""><span>Create account</span></a> </li> <li id="pt-login-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Special:UserLogin&amp;returnto=Area" title="You&#039;re encouraged to log in; however, it&#039;s not mandatory. [o]" accesskey="o" class=""><span>Log in</span></a> </li> </ul> </div> </div> </div> <div id="vector-user-links-dropdown" class="vector-dropdown vector-user-menu vector-button-flush-right vector-user-menu-logged-out" title="Log in and more options" > <input type="checkbox" id="vector-user-links-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-user-links-dropdown" class="vector-dropdown-checkbox " aria-label="Personal tools" > <label id="vector-user-links-dropdown-label" for="vector-user-links-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-ellipsis mw-ui-icon-wikimedia-ellipsis"></span> <span class="vector-dropdown-label-text">Personal tools</span> </label> <div class="vector-dropdown-content"> <div id="p-personal" class="vector-menu mw-portlet mw-portlet-personal user-links-collapsible-item" title="User menu" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport" class="user-links-collapsible-item mw-list-item"><a href="https://donate.wikimedia.org/wiki/Special:FundraiserRedirector?utm_source=donate&amp;utm_medium=sidebar&amp;utm_campaign=C13_en.wikipedia.org&amp;uselang=en"><span>Donate</span></a></li><li id="pt-createaccount" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=Special:CreateAccount&amp;returnto=Area" title="You are encouraged to create an account and log in; however, it is not mandatory"><span class="vector-icon mw-ui-icon-userAdd mw-ui-icon-wikimedia-userAdd"></span> <span>Create account</span></a></li><li id="pt-login" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=Special:UserLogin&amp;returnto=Area" title="You&#039;re encouraged to log in; however, it&#039;s not mandatory. [o]" accesskey="o"><span class="vector-icon mw-ui-icon-logIn mw-ui-icon-wikimedia-logIn"></span> <span>Log in</span></a></li> </ul> </div> </div> <div id="p-user-menu-anon-editor" class="vector-menu mw-portlet mw-portlet-user-menu-anon-editor" > <div class="vector-menu-heading"> Pages for logged out editors <a href="/wiki/Help:Introduction" aria-label="Learn more about editing"><span>learn more</span></a> </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-anoncontribs" class="mw-list-item"><a href="/wiki/Special:MyContributions" title="A list of edits made from this IP address [y]" accesskey="y"><span>Contributions</span></a></li><li id="pt-anontalk" class="mw-list-item"><a href="/wiki/Special:MyTalk" title="Discussion about edits from this IP address [n]" accesskey="n"><span>Talk</span></a></li> </ul> </div> </div> </div> </div> </nav> </div> </header> </div> <div class="mw-page-container"> <div class="mw-page-container-inner"> <div class="vector-sitenotice-container"> <div id="siteNotice"><!-- CentralNotice --></div> </div> <div class="vector-column-start"> <div class="vector-main-menu-container"> <div id="mw-navigation"> <nav id="mw-panel" class="vector-main-menu-landmark" aria-label="Site"> <div id="vector-main-menu-pinned-container" class="vector-pinned-container"> </div> </nav> </div> </div> <div class="vector-sticky-pinned-container"> <nav id="mw-panel-toc" aria-label="Contents" data-event-name="ui.sidebar-toc" class="mw-table-of-contents-container vector-toc-landmark"> <div id="vector-toc-pinned-container" class="vector-pinned-container"> <div id="vector-toc" class="vector-toc vector-pinnable-element"> <div class="vector-pinnable-header vector-toc-pinnable-header vector-pinnable-header-pinned" data-feature-name="toc-pinned" data-pinnable-element-id="vector-toc" > <h2 class="vector-pinnable-header-label">Contents</h2> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-toc.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-toc.unpin">hide</button> </div> <ul class="vector-toc-contents" id="mw-panel-toc-list"> <li id="toc-mw-content-text" class="vector-toc-list-item vector-toc-level-1"> <a href="#" class="vector-toc-link"> <div class="vector-toc-text">(Top)</div> </a> </li> <li id="toc-Formal_definition" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Formal_definition"> <div class="vector-toc-text"> <span class="vector-toc-numb">1</span> <span>Formal definition</span> </div> </a> <ul id="toc-Formal_definition-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Units" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Units"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Units</span> </div> </a> <button aria-controls="toc-Units-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Units subsection</span> </button> <ul id="toc-Units-sublist" class="vector-toc-list"> <li id="toc-Conversions" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Conversions"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.1</span> <span>Conversions</span> </div> </a> <ul id="toc-Conversions-sublist" class="vector-toc-list"> <li id="toc-Non-metric_units" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Non-metric_units"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.1.1</span> <span>Non-metric units</span> </div> </a> <ul id="toc-Non-metric_units-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Other_units_including_historical" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Other_units_including_historical"> <div class="vector-toc-text"> <span class="vector-toc-numb">2.2</span> <span>Other units including historical</span> </div> </a> <ul id="toc-Other_units_including_historical-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-History" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#History"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>History</span> </div> </a> <button aria-controls="toc-History-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle History subsection</span> </button> <ul id="toc-History-sublist" class="vector-toc-list"> <li id="toc-Circle_area" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Circle_area"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.1</span> <span>Circle area</span> </div> </a> <ul id="toc-Circle_area-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Triangle_area" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Triangle_area"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.2</span> <span>Triangle area</span> </div> </a> <ul id="toc-Triangle_area-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Quadrilateral_area" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Quadrilateral_area"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.3</span> <span>Quadrilateral area</span> </div> </a> <ul id="toc-Quadrilateral_area-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-General_polygon_area" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#General_polygon_area"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.4</span> <span>General polygon area</span> </div> </a> <ul id="toc-General_polygon_area-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Areas_determined_using_calculus" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Areas_determined_using_calculus"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.5</span> <span>Areas determined using calculus</span> </div> </a> <ul id="toc-Areas_determined_using_calculus-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Area_formulas" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Area_formulas"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Area formulas</span> </div> </a> <button aria-controls="toc-Area_formulas-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Area formulas subsection</span> </button> <ul id="toc-Area_formulas-sublist" class="vector-toc-list"> <li id="toc-Polygon_formulas" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Polygon_formulas"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.1</span> <span>Polygon formulas</span> </div> </a> <ul id="toc-Polygon_formulas-sublist" class="vector-toc-list"> <li id="toc-Rectangles" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Rectangles"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.1.1</span> <span>Rectangles</span> </div> </a> <ul id="toc-Rectangles-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Dissection,_parallelograms,_and_triangles" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Dissection,_parallelograms,_and_triangles"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.1.2</span> <span>Dissection, parallelograms, and triangles</span> </div> </a> <ul id="toc-Dissection,_parallelograms,_and_triangles-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Area_of_curved_shapes" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Area_of_curved_shapes"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2</span> <span>Area of curved shapes</span> </div> </a> <ul id="toc-Area_of_curved_shapes-sublist" class="vector-toc-list"> <li id="toc-Circles" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Circles"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2.1</span> <span>Circles</span> </div> </a> <ul id="toc-Circles-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Ellipses" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Ellipses"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2.2</span> <span>Ellipses</span> </div> </a> <ul id="toc-Ellipses-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Non-planar_surface_area" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Non-planar_surface_area"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.3</span> <span>Non-planar surface area</span> </div> </a> <ul id="toc-Non-planar_surface_area-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-General_formulas" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#General_formulas"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.4</span> <span>General formulas</span> </div> </a> <ul id="toc-General_formulas-sublist" class="vector-toc-list"> <li id="toc-Areas_of_2-dimensional_figures" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Areas_of_2-dimensional_figures"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.4.1</span> <span>Areas of 2-dimensional figures</span> </div> </a> <ul id="toc-Areas_of_2-dimensional_figures-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Area_in_calculus" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Area_in_calculus"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.4.2</span> <span>Area in calculus</span> </div> </a> <ul id="toc-Area_in_calculus-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Bounded_area_between_two_quadratic_functions" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Bounded_area_between_two_quadratic_functions"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.4.3</span> <span>Bounded area between two quadratic functions</span> </div> </a> <ul id="toc-Bounded_area_between_two_quadratic_functions-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Surface_area_of_3-dimensional_figures" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Surface_area_of_3-dimensional_figures"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.4.4</span> <span>Surface area of 3-dimensional figures</span> </div> </a> <ul id="toc-Surface_area_of_3-dimensional_figures-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-General_formula_for_surface_area" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#General_formula_for_surface_area"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.4.5</span> <span>General formula for surface area</span> </div> </a> <ul id="toc-General_formula_for_surface_area-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-List_of_formulas" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#List_of_formulas"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.5</span> <span>List of formulas</span> </div> </a> <ul id="toc-List_of_formulas-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Relation_of_area_to_perimeter" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Relation_of_area_to_perimeter"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.6</span> <span>Relation of area to perimeter</span> </div> </a> <ul id="toc-Relation_of_area_to_perimeter-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Fractals" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Fractals"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.7</span> <span>Fractals</span> </div> </a> <ul id="toc-Fractals-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Area_bisectors" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Area_bisectors"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>Area bisectors</span> </div> </a> <ul id="toc-Area_bisectors-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Optimization" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#Optimization"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Optimization</span> </div> </a> <ul id="toc-Optimization-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">9</span> <span>External links</span> </div> </a> <ul id="toc-External_links-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Toggle the table of contents</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Area</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Go to an article in another language. Available in 164 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-164" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">164 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-kbd mw-list-item"><a href="https://kbd.wikipedia.org/wiki/%D0%A9%D3%80%D1%8B%D0%BF%D3%80%D1%8D_%D0%B8%D0%BD%D0%B0%D0%B3%D1%8A" title="ЩӀыпӀэ инагъ – Kabardian" lang="kbd" hreflang="kbd" data-title="ЩӀыпӀэ инагъ" data-language-autonym="Адыгэбзэ" data-language-local-name="Kabardian" class="interlanguage-link-target"><span>Адыгэбзэ</span></a></li><li class="interlanguage-link interwiki-af mw-list-item"><a href="https://af.wikipedia.org/wiki/Oppervlakte" title="Oppervlakte – Afrikaans" lang="af" hreflang="af" data-title="Oppervlakte" data-language-autonym="Afrikaans" data-language-local-name="Afrikaans" class="interlanguage-link-target"><span>Afrikaans</span></a></li><li class="interlanguage-link interwiki-als mw-list-item"><a href="https://als.wikipedia.org/wiki/Fl%C3%A4cheninhalt" title="Flächeninhalt – Alemannic" lang="gsw" hreflang="gsw" data-title="Flächeninhalt" data-language-autonym="Alemannisch" data-language-local-name="Alemannic" class="interlanguage-link-target"><span>Alemannisch</span></a></li><li class="interlanguage-link interwiki-anp mw-list-item"><a href="https://anp.wikipedia.org/wiki/%E0%A4%95%E0%A5%8D%E0%A4%B7%E0%A5%87%E0%A4%A4%E0%A5%8D%E0%A4%B0%E0%A4%AB%E0%A4%B2" title="क्षेत्रफल – Angika" lang="anp" hreflang="anp" data-title="क्षेत्रफल" data-language-autonym="अंगिका" data-language-local-name="Angika" class="interlanguage-link-target"><span>अंगिका</span></a></li><li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D9%85%D8%B3%D8%A7%D8%AD%D8%A9" title="مساحة – Arabic" lang="ar" hreflang="ar" data-title="مساحة" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-an mw-list-item"><a href="https://an.wikipedia.org/wiki/Aria" title="Aria – Aragonese" lang="an" hreflang="an" data-title="Aria" data-language-autonym="Aragonés" data-language-local-name="Aragonese" class="interlanguage-link-target"><span>Aragonés</span></a></li><li class="interlanguage-link interwiki-arc mw-list-item"><a href="https://arc.wikipedia.org/wiki/%DC%AB%DC%9B%DC%9D%DC%9A%DC%98%DC%AC%DC%90" title="ܫܛܝܚܘܬܐ – Aramaic" lang="arc" hreflang="arc" data-title="ܫܛܝܚܘܬܐ" data-language-autonym="ܐܪܡܝܐ" data-language-local-name="Aramaic" class="interlanguage-link-target"><span>ܐܪܡܝܐ</span></a></li><li class="interlanguage-link interwiki-as mw-list-item"><a href="https://as.wikipedia.org/wiki/%E0%A6%95%E0%A7%8D%E0%A6%B7%E0%A7%87%E0%A6%A4%E0%A7%8D%E0%A7%B0%E0%A6%AB%E0%A6%B2" title="ক্ষেত্ৰফল – Assamese" lang="as" hreflang="as" data-title="ক্ষেত্ৰফল" data-language-autonym="অসমীয়া" data-language-local-name="Assamese" class="interlanguage-link-target"><span>অসমীয়া</span></a></li><li class="interlanguage-link interwiki-ast mw-list-item"><a href="https://ast.wikipedia.org/wiki/%C3%81rea_(xeometr%C3%ADa)" title="Área (xeometría) – Asturian" lang="ast" hreflang="ast" data-title="Área (xeometría)" data-language-autonym="Asturianu" data-language-local-name="Asturian" class="interlanguage-link-target"><span>Asturianu</span></a></li><li class="interlanguage-link interwiki-awa mw-list-item"><a href="https://awa.wikipedia.org/wiki/%E0%A4%95%E0%A5%8D%E0%A4%B7%E0%A5%87%E0%A4%A4%E0%A5%8D%E0%A4%B0%E0%A4%AB%E0%A4%B2" title="क्षेत्रफल – Awadhi" lang="awa" hreflang="awa" data-title="क्षेत्रफल" data-language-autonym="अवधी" data-language-local-name="Awadhi" class="interlanguage-link-target"><span>अवधी</span></a></li><li class="interlanguage-link interwiki-gn mw-list-item"><a href="https://gn.wikipedia.org/wiki/Tendaha" title="Tendaha – Guarani" lang="gn" hreflang="gn" data-title="Tendaha" data-language-autonym="Avañe&#039;ẽ" data-language-local-name="Guarani" class="interlanguage-link-target"><span>Avañe'ẽ</span></a></li><li class="interlanguage-link interwiki-av mw-list-item"><a href="https://av.wikipedia.org/wiki/%D0%9F%D0%BB%D0%BE%D1%89%D0%B0%D0%B4%D1%8C" title="Площадь – Avaric" lang="av" hreflang="av" data-title="Площадь" data-language-autonym="Авар" data-language-local-name="Avaric" class="interlanguage-link-target"><span>Авар</span></a></li><li class="interlanguage-link interwiki-az mw-list-item"><a href="https://az.wikipedia.org/wiki/Sah%C9%99_(%C3%B6l%C3%A7%C3%BC_parametri)" title="Sahə (ölçü parametri) – Azerbaijani" lang="az" hreflang="az" data-title="Sahə (ölçü parametri)" data-language-autonym="Azərbaycanca" data-language-local-name="Azerbaijani" class="interlanguage-link-target"><span>Azərbaycanca</span></a></li><li class="interlanguage-link interwiki-azb mw-list-item"><a href="https://azb.wikipedia.org/wiki/%D9%85%D8%B3%D8%A7%D8%AD%D8%AA" title="مساحت – South Azerbaijani" lang="azb" hreflang="azb" data-title="مساحت" data-language-autonym="تۆرکجه" data-language-local-name="South Azerbaijani" class="interlanguage-link-target"><span>تۆرکجه</span></a></li><li class="interlanguage-link interwiki-bn mw-list-item"><a href="https://bn.wikipedia.org/wiki/%E0%A6%95%E0%A7%8D%E0%A6%B7%E0%A7%87%E0%A6%A4%E0%A7%8D%E0%A6%B0%E0%A6%AB%E0%A6%B2" title="ক্ষেত্রফল – Bangla" lang="bn" hreflang="bn" data-title="ক্ষেত্রফল" data-language-autonym="বাংলা" data-language-local-name="Bangla" class="interlanguage-link-target"><span>বাংলা</span></a></li><li class="interlanguage-link interwiki-zh-min-nan mw-list-item"><a href="https://zh-min-nan.wikipedia.org/wiki/Bi%C4%81n-chek" title="Biān-chek – Minnan" lang="nan" hreflang="nan" data-title="Biān-chek" data-language-autonym="閩南語 / Bân-lâm-gú" data-language-local-name="Minnan" class="interlanguage-link-target"><span>閩南語 / Bân-lâm-gú</span></a></li><li class="interlanguage-link interwiki-ba mw-list-item"><a href="https://ba.wikipedia.org/wiki/%D0%9C%D0%B0%D0%B9%D2%99%D0%B0%D0%BD" title="Майҙан – Bashkir" lang="ba" hreflang="ba" data-title="Майҙан" data-language-autonym="Башҡортса" data-language-local-name="Bashkir" class="interlanguage-link-target"><span>Башҡортса</span></a></li><li class="interlanguage-link interwiki-be mw-list-item"><a href="https://be.wikipedia.org/wiki/%D0%9F%D0%BB%D0%BE%D1%88%D1%87%D0%B0" title="Плошча – Belarusian" lang="be" hreflang="be" data-title="Плошча" data-language-autonym="Беларуская" data-language-local-name="Belarusian" class="interlanguage-link-target"><span>Беларуская</span></a></li><li class="interlanguage-link interwiki-be-x-old mw-list-item"><a href="https://be-tarask.wikipedia.org/wiki/%D0%9F%D0%BB%D0%BE%D1%88%D1%87%D0%B0" title="Плошча – Belarusian (Taraškievica orthography)" lang="be-tarask" hreflang="be-tarask" data-title="Плошча" data-language-autonym="Беларуская (тарашкевіца)" data-language-local-name="Belarusian (Taraškievica orthography)" class="interlanguage-link-target"><span>Беларуская (тарашкевіца)</span></a></li><li class="interlanguage-link interwiki-bh mw-list-item"><a href="https://bh.wikipedia.org/wiki/%E0%A4%95%E0%A5%8D%E0%A4%B7%E0%A5%87%E0%A4%A4%E0%A5%8D%E0%A4%B0%E0%A4%AB%E0%A4%B2" title="क्षेत्रफल – Bhojpuri" lang="bh" hreflang="bh" data-title="क्षेत्रफल" data-language-autonym="भोजपुरी" data-language-local-name="Bhojpuri" class="interlanguage-link-target"><span>भोजपुरी</span></a></li><li class="interlanguage-link interwiki-bcl mw-list-item"><a href="https://bcl.wikipedia.org/wiki/Hiwas" title="Hiwas – Central Bikol" lang="bcl" hreflang="bcl" data-title="Hiwas" data-language-autonym="Bikol Central" data-language-local-name="Central Bikol" class="interlanguage-link-target"><span>Bikol Central</span></a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/%D0%9F%D0%BB%D0%BE%D1%89" title="Площ – Bulgarian" lang="bg" hreflang="bg" data-title="Площ" data-language-autonym="Български" data-language-local-name="Bulgarian" class="interlanguage-link-target"><span>Български</span></a></li><li class="interlanguage-link interwiki-bar mw-list-item"><a href="https://bar.wikipedia.org/wiki/Fl%C3%A4chn" title="Flächn – Bavarian" lang="bar" hreflang="bar" data-title="Flächn" data-language-autonym="Boarisch" data-language-local-name="Bavarian" class="interlanguage-link-target"><span>Boarisch</span></a></li><li class="interlanguage-link interwiki-bs mw-list-item"><a href="https://bs.wikipedia.org/wiki/Povr%C5%A1ina" title="Površina – Bosnian" lang="bs" hreflang="bs" data-title="Površina" data-language-autonym="Bosanski" data-language-local-name="Bosnian" class="interlanguage-link-target"><span>Bosanski</span></a></li><li class="interlanguage-link interwiki-br mw-list-item"><a href="https://br.wikipedia.org/wiki/Gorread" title="Gorread – Breton" lang="br" hreflang="br" data-title="Gorread" data-language-autonym="Brezhoneg" data-language-local-name="Breton" class="interlanguage-link-target"><span>Brezhoneg</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/%C3%80rea" title="Àrea – Catalan" lang="ca" hreflang="ca" data-title="Àrea" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cv mw-list-item"><a href="https://cv.wikipedia.org/wiki/%D0%9B%D0%B0%D0%BF%D1%82%C4%83%D0%BA" title="Лаптăк – Chuvash" lang="cv" hreflang="cv" data-title="Лаптăк" data-language-autonym="Чӑвашла" data-language-local-name="Chuvash" class="interlanguage-link-target"><span>Чӑвашла</span></a></li><li class="interlanguage-link interwiki-ceb mw-list-item"><a href="https://ceb.wikipedia.org/wiki/Langyab" title="Langyab – Cebuano" lang="ceb" hreflang="ceb" data-title="Langyab" data-language-autonym="Cebuano" data-language-local-name="Cebuano" class="interlanguage-link-target"><span>Cebuano</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Obsah" title="Obsah – Czech" lang="cs" hreflang="cs" data-title="Obsah" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-sn mw-list-item"><a href="https://sn.wikipedia.org/wiki/Nharaunda" title="Nharaunda – Shona" lang="sn" hreflang="sn" data-title="Nharaunda" data-language-autonym="ChiShona" data-language-local-name="Shona" class="interlanguage-link-target"><span>ChiShona</span></a></li><li class="interlanguage-link interwiki-cy mw-list-item"><a href="https://cy.wikipedia.org/wiki/Arwynebedd" title="Arwynebedd – Welsh" lang="cy" hreflang="cy" data-title="Arwynebedd" data-language-autonym="Cymraeg" data-language-local-name="Welsh" class="interlanguage-link-target"><span>Cymraeg</span></a></li><li class="interlanguage-link interwiki-da mw-list-item"><a href="https://da.wikipedia.org/wiki/Areal" title="Areal – Danish" lang="da" hreflang="da" data-title="Areal" data-language-autonym="Dansk" data-language-local-name="Danish" class="interlanguage-link-target"><span>Dansk</span></a></li><li class="interlanguage-link interwiki-ary mw-list-item"><a href="https://ary.wikipedia.org/wiki/%D8%AA%D9%8A%D8%B3%D8%A7%D8%B9" title="تيساع – Moroccan Arabic" lang="ary" hreflang="ary" data-title="تيساع" data-language-autonym="الدارجة" data-language-local-name="Moroccan Arabic" class="interlanguage-link-target"><span>الدارجة</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Fl%C3%A4cheninhalt" title="Flächeninhalt – German" lang="de" hreflang="de" data-title="Flächeninhalt" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-dv mw-list-item"><a href="https://dv.wikipedia.org/wiki/%DE%87%DE%A6%DE%86%DE%A6%DE%89%DE%A8%DE%82%DE%B0" title="އަކަމިން – Divehi" lang="dv" hreflang="dv" data-title="އަކަމިން" data-language-autonym="ދިވެހިބަސް" data-language-local-name="Divehi" class="interlanguage-link-target"><span>ދިވެހިބަސް</span></a></li><li class="interlanguage-link interwiki-dsb mw-list-item"><a href="https://dsb.wikipedia.org/wiki/Wop%C5%9Bimje%C5%9Be_p%C5%82oni" title="Wopśimjeśe płoni – Lower Sorbian" lang="dsb" hreflang="dsb" data-title="Wopśimjeśe płoni" data-language-autonym="Dolnoserbski" data-language-local-name="Lower Sorbian" class="interlanguage-link-target"><span>Dolnoserbski</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/Pindala" title="Pindala – Estonian" lang="et" hreflang="et" data-title="Pindala" data-language-autonym="Eesti" data-language-local-name="Estonian" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-el mw-list-item"><a href="https://el.wikipedia.org/wiki/%CE%95%CE%BC%CE%B2%CE%B1%CE%B4%CF%8C%CE%BD" title="Εμβαδόν – Greek" lang="el" hreflang="el" data-title="Εμβαδόν" data-language-autonym="Ελληνικά" data-language-local-name="Greek" class="interlanguage-link-target"><span>Ελληνικά</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/%C3%81rea" title="Área – Spanish" lang="es" hreflang="es" data-title="Área" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/Areo" title="Areo – Esperanto" lang="eo" hreflang="eo" data-title="Areo" data-language-autonym="Esperanto" data-language-local-name="Esperanto" class="interlanguage-link-target"><span>Esperanto</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Azalera" title="Azalera – Basque" lang="eu" hreflang="eu" data-title="Azalera" data-language-autonym="Euskara" data-language-local-name="Basque" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D9%85%D8%B3%D8%A7%D8%AD%D8%AA" title="مساحت – Persian" lang="fa" hreflang="fa" data-title="مساحت" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-hif mw-list-item"><a href="https://hif.wikipedia.org/wiki/Area" title="Area – Fiji Hindi" lang="hif" hreflang="hif" data-title="Area" data-language-autonym="Fiji Hindi" data-language-local-name="Fiji Hindi" class="interlanguage-link-target"><span>Fiji Hindi</span></a></li><li class="interlanguage-link interwiki-fo mw-list-item"><a href="https://fo.wikipedia.org/wiki/V%C3%ADdd" title="Vídd – Faroese" lang="fo" hreflang="fo" data-title="Vídd" data-language-autonym="Føroyskt" data-language-local-name="Faroese" class="interlanguage-link-target"><span>Føroyskt</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Aire_(g%C3%A9om%C3%A9trie)" title="Aire (géométrie) – French" lang="fr" hreflang="fr" data-title="Aire (géométrie)" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-fy mw-list-item"><a href="https://fy.wikipedia.org/wiki/Oerflak" title="Oerflak – Western Frisian" lang="fy" hreflang="fy" data-title="Oerflak" data-language-autonym="Frysk" data-language-local-name="Western Frisian" class="interlanguage-link-target"><span>Frysk</span></a></li><li class="interlanguage-link interwiki-gv mw-list-item"><a href="https://gv.wikipedia.org/wiki/Eaghtyr" title="Eaghtyr – Manx" lang="gv" hreflang="gv" data-title="Eaghtyr" data-language-autonym="Gaelg" data-language-local-name="Manx" class="interlanguage-link-target"><span>Gaelg</span></a></li><li class="interlanguage-link interwiki-gd mw-list-item"><a href="https://gd.wikipedia.org/wiki/Farsaingeachd" title="Farsaingeachd – Scottish Gaelic" lang="gd" hreflang="gd" data-title="Farsaingeachd" data-language-autonym="Gàidhlig" data-language-local-name="Scottish Gaelic" class="interlanguage-link-target"><span>Gàidhlig</span></a></li><li class="interlanguage-link interwiki-gl mw-list-item"><a href="https://gl.wikipedia.org/wiki/%C3%81rea" title="Área – Galician" lang="gl" hreflang="gl" data-title="Área" data-language-autonym="Galego" data-language-local-name="Galician" class="interlanguage-link-target"><span>Galego</span></a></li><li class="interlanguage-link interwiki-gan mw-list-item"><a href="https://gan.wikipedia.org/wiki/%E9%9D%A2%E7%A9%8D" title="面積 – Gan" lang="gan" hreflang="gan" data-title="面積" data-language-autonym="贛語" data-language-local-name="Gan" class="interlanguage-link-target"><span>贛語</span></a></li><li class="interlanguage-link interwiki-gu mw-list-item"><a href="https://gu.wikipedia.org/wiki/%E0%AA%95%E0%AB%8D%E0%AA%B7%E0%AB%87%E0%AA%A4%E0%AB%8D%E0%AA%B0%E0%AA%AB%E0%AA%B3" title="ક્ષેત્રફળ – Gujarati" lang="gu" hreflang="gu" data-title="ક્ષેત્રફળ" data-language-autonym="ગુજરાતી" data-language-local-name="Gujarati" class="interlanguage-link-target"><span>ગુજરાતી</span></a></li><li class="interlanguage-link interwiki-hak mw-list-item"><a href="https://hak.wikipedia.org/wiki/Mien-chit" title="Mien-chit – Hakka Chinese" lang="hak" hreflang="hak" data-title="Mien-chit" data-language-autonym="客家語 / Hak-kâ-ngî" data-language-local-name="Hakka Chinese" class="interlanguage-link-target"><span>客家語 / Hak-kâ-ngî</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EB%84%93%EC%9D%B4" title="넓이 – Korean" lang="ko" hreflang="ko" data-title="넓이" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-haw mw-list-item"><a href="https://haw.wikipedia.org/wiki/%CA%BBAlea" title="ʻAlea – Hawaiian" lang="haw" hreflang="haw" data-title="ʻAlea" data-language-autonym="Hawaiʻi" data-language-local-name="Hawaiian" class="interlanguage-link-target"><span>Hawaiʻi</span></a></li><li class="interlanguage-link interwiki-hy mw-list-item"><a href="https://hy.wikipedia.org/wiki/%D5%84%D5%A1%D5%AF%D5%A5%D6%80%D5%A5%D5%BD" title="Մակերես – Armenian" lang="hy" hreflang="hy" data-title="Մակերես" data-language-autonym="Հայերեն" data-language-local-name="Armenian" class="interlanguage-link-target"><span>Հայերեն</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%95%E0%A5%8D%E0%A4%B7%E0%A5%87%E0%A4%A4%E0%A5%8D%E0%A4%B0%E0%A4%AB%E0%A4%B2" title="क्षेत्रफल – Hindi" lang="hi" hreflang="hi" data-title="क्षेत्रफल" data-language-autonym="हिन्दी" data-language-local-name="Hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-hsb mw-list-item"><a href="https://hsb.wikipedia.org/wiki/Wobsah_p%C5%99estrjenje" title="Wobsah přestrjenje – Upper Sorbian" lang="hsb" hreflang="hsb" data-title="Wobsah přestrjenje" data-language-autonym="Hornjoserbsce" data-language-local-name="Upper Sorbian" class="interlanguage-link-target"><span>Hornjoserbsce</span></a></li><li class="interlanguage-link interwiki-hr mw-list-item"><a href="https://hr.wikipedia.org/wiki/Povr%C5%A1ina" title="Površina – Croatian" lang="hr" hreflang="hr" data-title="Površina" data-language-autonym="Hrvatski" data-language-local-name="Croatian" class="interlanguage-link-target"><span>Hrvatski</span></a></li><li class="interlanguage-link interwiki-io mw-list-item"><a href="https://io.wikipedia.org/wiki/Areo" title="Areo – Ido" lang="io" hreflang="io" data-title="Areo" data-language-autonym="Ido" data-language-local-name="Ido" class="interlanguage-link-target"><span>Ido</span></a></li><li class="interlanguage-link interwiki-ilo mw-list-item"><a href="https://ilo.wikipedia.org/wiki/Kalawa" title="Kalawa – Iloko" lang="ilo" hreflang="ilo" data-title="Kalawa" data-language-autonym="Ilokano" data-language-local-name="Iloko" class="interlanguage-link-target"><span>Ilokano</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Luas" title="Luas – Indonesian" lang="id" hreflang="id" data-title="Luas" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-ia mw-list-item"><a href="https://ia.wikipedia.org/wiki/Area" title="Area – Interlingua" lang="ia" hreflang="ia" data-title="Area" data-language-autonym="Interlingua" data-language-local-name="Interlingua" class="interlanguage-link-target"><span>Interlingua</span></a></li><li class="interlanguage-link interwiki-os mw-list-item"><a href="https://os.wikipedia.org/wiki/%D0%A4%C3%A6%D0%B7%D1%83%D0%B0%D1%82" title="Фæзуат – Ossetic" lang="os" hreflang="os" data-title="Фæзуат" data-language-autonym="Ирон" data-language-local-name="Ossetic" class="interlanguage-link-target"><span>Ирон</span></a></li><li class="interlanguage-link interwiki-is mw-list-item"><a href="https://is.wikipedia.org/wiki/Flatarm%C3%A1l" title="Flatarmál – Icelandic" lang="is" hreflang="is" data-title="Flatarmál" data-language-autonym="Íslenska" data-language-local-name="Icelandic" class="interlanguage-link-target"><span>Íslenska</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Area" title="Area – Italian" lang="it" hreflang="it" data-title="Area" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/%D7%A9%D7%98%D7%97" title="שטח – Hebrew" lang="he" hreflang="he" data-title="שטח" data-language-autonym="עברית" data-language-local-name="Hebrew" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-jv mw-list-item"><a href="https://jv.wikipedia.org/wiki/Jembar" title="Jembar – Javanese" lang="jv" hreflang="jv" data-title="Jembar" data-language-autonym="Jawa" data-language-local-name="Javanese" class="interlanguage-link-target"><span>Jawa</span></a></li><li class="interlanguage-link interwiki-ka mw-list-item"><a href="https://ka.wikipedia.org/wiki/%E1%83%A4%E1%83%90%E1%83%A0%E1%83%97%E1%83%9D%E1%83%91%E1%83%98" title="ფართობი – Georgian" lang="ka" hreflang="ka" data-title="ფართობი" data-language-autonym="ქართული" data-language-local-name="Georgian" class="interlanguage-link-target"><span>ქართული</span></a></li><li class="interlanguage-link interwiki-kk mw-list-item"><a href="https://kk.wikipedia.org/wiki/%D0%90%D1%83%D0%B4%D0%B0%D0%BD_(%D0%B3%D0%B5%D0%BE%D0%BC%D0%B5%D1%82%D1%80%D0%B8%D1%8F)" title="Аудан (геометрия) – Kazakh" lang="kk" hreflang="kk" data-title="Аудан (геометрия)" data-language-autonym="Қазақша" data-language-local-name="Kazakh" class="interlanguage-link-target"><span>Қазақша</span></a></li><li class="interlanguage-link interwiki-kw mw-list-item"><a href="https://kw.wikipedia.org/wiki/Enep_(fysegieth)" title="Enep (fysegieth) – Cornish" lang="kw" hreflang="kw" data-title="Enep (fysegieth)" data-language-autonym="Kernowek" data-language-local-name="Cornish" class="interlanguage-link-target"><span>Kernowek</span></a></li><li class="interlanguage-link interwiki-sw mw-list-item"><a href="https://sw.wikipedia.org/wiki/Eneo" title="Eneo – Swahili" lang="sw" hreflang="sw" data-title="Eneo" data-language-autonym="Kiswahili" data-language-local-name="Swahili" class="interlanguage-link-target"><span>Kiswahili</span></a></li><li class="interlanguage-link interwiki-ku mw-list-item"><a href="https://ku.wikipedia.org/wiki/R%C3%BBerd" title="Rûerd – Kurdish" lang="ku" hreflang="ku" data-title="Rûerd" data-language-autonym="Kurdî" data-language-local-name="Kurdish" class="interlanguage-link-target"><span>Kurdî</span></a></li><li class="interlanguage-link interwiki-ky mw-list-item"><a href="https://ky.wikipedia.org/wiki/%D0%90%D1%8F%D0%BD%D1%82" title="Аянт – Kyrgyz" lang="ky" hreflang="ky" data-title="Аянт" data-language-autonym="Кыргызча" data-language-local-name="Kyrgyz" class="interlanguage-link-target"><span>Кыргызча</span></a></li><li class="interlanguage-link interwiki-lo mw-list-item"><a href="https://lo.wikipedia.org/wiki/%E0%BB%80%E0%BA%99%E0%BA%B7%E0%BB%89%E0%BA%AD%E0%BA%97%E0%BA%B5%E0%BB%88" title="ເນື້ອທີ່ – Lao" lang="lo" hreflang="lo" data-title="ເນື້ອທີ່" data-language-autonym="ລາວ" data-language-local-name="Lao" class="interlanguage-link-target"><span>ລາວ</span></a></li><li class="interlanguage-link interwiki-la mw-list-item"><a href="https://la.wikipedia.org/wiki/Area_(geometria)" title="Area (geometria) – Latin" lang="la" hreflang="la" data-title="Area (geometria)" data-language-autonym="Latina" data-language-local-name="Latin" class="interlanguage-link-target"><span>Latina</span></a></li><li class="interlanguage-link interwiki-lv mw-list-item"><a href="https://lv.wikipedia.org/wiki/Laukums" title="Laukums – Latvian" lang="lv" hreflang="lv" data-title="Laukums" data-language-autonym="Latviešu" data-language-local-name="Latvian" class="interlanguage-link-target"><span>Latviešu</span></a></li><li class="interlanguage-link interwiki-lb mw-list-item"><a href="https://lb.wikipedia.org/wiki/Fl%C3%A4ch" title="Fläch – Luxembourgish" lang="lb" hreflang="lb" data-title="Fläch" data-language-autonym="Lëtzebuergesch" data-language-local-name="Luxembourgish" class="interlanguage-link-target"><span>Lëtzebuergesch</span></a></li><li class="interlanguage-link interwiki-lt mw-list-item"><a href="https://lt.wikipedia.org/wiki/Plotas" title="Plotas – Lithuanian" lang="lt" hreflang="lt" data-title="Plotas" data-language-autonym="Lietuvių" data-language-local-name="Lithuanian" class="interlanguage-link-target"><span>Lietuvių</span></a></li><li class="interlanguage-link interwiki-lij mw-list-item"><a href="https://lij.wikipedia.org/wiki/Area" title="Area – Ligurian" lang="lij" hreflang="lij" data-title="Area" data-language-autonym="Ligure" data-language-local-name="Ligurian" class="interlanguage-link-target"><span>Ligure</span></a></li><li class="interlanguage-link interwiki-li mw-list-item"><a href="https://li.wikipedia.org/wiki/Oppervlak" title="Oppervlak – Limburgish" lang="li" hreflang="li" data-title="Oppervlak" data-language-autonym="Limburgs" data-language-local-name="Limburgish" class="interlanguage-link-target"><span>Limburgs</span></a></li><li class="interlanguage-link interwiki-ln mw-list-item"><a href="https://ln.wikipedia.org/wiki/Etando" title="Etando – Lingala" lang="ln" hreflang="ln" data-title="Etando" data-language-autonym="Lingála" data-language-local-name="Lingala" class="interlanguage-link-target"><span>Lingála</span></a></li><li class="interlanguage-link interwiki-lmo mw-list-item"><a href="https://lmo.wikipedia.org/wiki/Area" title="Area – Lombard" lang="lmo" hreflang="lmo" data-title="Area" data-language-autonym="Lombard" data-language-local-name="Lombard" class="interlanguage-link-target"><span>Lombard</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/Ter%C3%BClet_(matematika)" title="Terület (matematika) – Hungarian" lang="hu" hreflang="hu" data-title="Terület (matematika)" data-language-autonym="Magyar" data-language-local-name="Hungarian" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-mai mw-list-item"><a href="https://mai.wikipedia.org/wiki/%E0%A4%95%E0%A5%8D%E0%A4%B7%E0%A5%87%E0%A4%A4%E0%A5%8D%E0%A4%B0%E0%A4%AB%E0%A4%B2" title="क्षेत्रफल – Maithili" lang="mai" hreflang="mai" data-title="क्षेत्रफल" data-language-autonym="मैथिली" data-language-local-name="Maithili" class="interlanguage-link-target"><span>मैथिली</span></a></li><li class="interlanguage-link interwiki-mk mw-list-item"><a href="https://mk.wikipedia.org/wiki/%D0%9F%D0%BB%D0%BE%D1%88%D1%82%D0%B8%D0%BD%D0%B0" title="Плоштина – Macedonian" lang="mk" hreflang="mk" data-title="Плоштина" data-language-autonym="Македонски" data-language-local-name="Macedonian" class="interlanguage-link-target"><span>Македонски</span></a></li><li class="interlanguage-link interwiki-mg mw-list-item"><a href="https://mg.wikipedia.org/wiki/Velarantany" title="Velarantany – Malagasy" lang="mg" hreflang="mg" data-title="Velarantany" data-language-autonym="Malagasy" data-language-local-name="Malagasy" class="interlanguage-link-target"><span>Malagasy</span></a></li><li class="interlanguage-link interwiki-ml mw-list-item"><a href="https://ml.wikipedia.org/wiki/%E0%B4%B5%E0%B4%BF%E0%B4%B8%E0%B5%8D%E0%B4%A4%E0%B5%80%E0%B5%BC%E0%B4%A3%E0%B5%8D%E0%B4%A3%E0%B4%82" title="വിസ്തീർണ്ണം – Malayalam" lang="ml" hreflang="ml" data-title="വിസ്തീർണ്ണം" data-language-autonym="മലയാളം" data-language-local-name="Malayalam" class="interlanguage-link-target"><span>മലയാളം</span></a></li><li class="interlanguage-link interwiki-mr mw-list-item"><a href="https://mr.wikipedia.org/wiki/%E0%A4%95%E0%A5%8D%E0%A4%B7%E0%A5%87%E0%A4%A4%E0%A5%8D%E0%A4%B0%E0%A4%AB%E0%A4%B3" title="क्षेत्रफळ – Marathi" lang="mr" hreflang="mr" data-title="क्षेत्रफळ" data-language-autonym="मराठी" data-language-local-name="Marathi" class="interlanguage-link-target"><span>मराठी</span></a></li><li class="interlanguage-link interwiki-xmf mw-list-item"><a href="https://xmf.wikipedia.org/wiki/%E1%83%A4%E1%83%90%E1%83%A0%E1%83%97%E1%83%9D%E1%83%91%E1%83%98" title="ფართობი – Mingrelian" lang="xmf" hreflang="xmf" data-title="ფართობი" data-language-autonym="მარგალური" data-language-local-name="Mingrelian" class="interlanguage-link-target"><span>მარგალური</span></a></li><li class="interlanguage-link interwiki-arz mw-list-item"><a href="https://arz.wikipedia.org/wiki/%D9%85%D8%B3%D8%A7%D8%AD%D9%87" title="مساحه – Egyptian Arabic" lang="arz" hreflang="arz" data-title="مساحه" data-language-autonym="مصرى" data-language-local-name="Egyptian Arabic" class="interlanguage-link-target"><span>مصرى</span></a></li><li class="interlanguage-link interwiki-mzn mw-list-item"><a href="https://mzn.wikipedia.org/wiki/%DA%AF%D8%AA%DB%8C" title="گتی – Mazanderani" lang="mzn" hreflang="mzn" data-title="گتی" data-language-autonym="مازِرونی" data-language-local-name="Mazanderani" class="interlanguage-link-target"><span>مازِرونی</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Luas" title="Luas – Malay" lang="ms" hreflang="ms" data-title="Luas" data-language-autonym="Bahasa Melayu" data-language-local-name="Malay" class="interlanguage-link-target"><span>Bahasa Melayu</span></a></li><li class="interlanguage-link interwiki-mni mw-list-item"><a href="https://mni.wikipedia.org/wiki/%EA%AF%84%EA%AF%A5%EA%AF%9B%EA%AF%86%EA%AF%A5%EA%AF%8E%EA%AF%95" title="ꯄꯥꯛꯆꯥꯎꯕ – Manipuri" lang="mni" hreflang="mni" data-title="ꯄꯥꯛꯆꯥꯎꯕ" data-language-autonym="ꯃꯤꯇꯩ ꯂꯣꯟ" data-language-local-name="Manipuri" class="interlanguage-link-target"><span>ꯃꯤꯇꯩ ꯂꯣꯟ</span></a></li><li class="interlanguage-link interwiki-cdo mw-list-item"><a href="https://cdo.wikipedia.org/wiki/Mi%C3%AAng-c%C3%A9k" title="Miêng-cék – Mindong" lang="cdo" hreflang="cdo" data-title="Miêng-cék" data-language-autonym="閩東語 / Mìng-dĕ̤ng-ngṳ̄" data-language-local-name="Mindong" class="interlanguage-link-target"><span>閩東語 / Mìng-dĕ̤ng-ngṳ̄</span></a></li><li class="interlanguage-link interwiki-mwl mw-list-item"><a href="https://mwl.wikipedia.org/wiki/%C3%81ria" title="Ária – Mirandese" lang="mwl" hreflang="mwl" data-title="Ária" data-language-autonym="Mirandés" data-language-local-name="Mirandese" class="interlanguage-link-target"><span>Mirandés</span></a></li><li class="interlanguage-link interwiki-mn mw-list-item"><a href="https://mn.wikipedia.org/wiki/%D0%A2%D0%B0%D0%BB%D0%B1%D0%B0%D0%B9" title="Талбай – Mongolian" lang="mn" hreflang="mn" data-title="Талбай" data-language-autonym="Монгол" data-language-local-name="Mongolian" class="interlanguage-link-target"><span>Монгол</span></a></li><li class="interlanguage-link interwiki-my mw-list-item"><a href="https://my.wikipedia.org/wiki/%E1%80%A7%E1%80%9B%E1%80%AD%E1%80%9A%E1%80%AC" title="ဧရိယာ – Burmese" lang="my" hreflang="my" data-title="ဧရိယာ" data-language-autonym="မြန်မာဘာသာ" data-language-local-name="Burmese" class="interlanguage-link-target"><span>မြန်မာဘာသာ</span></a></li><li class="interlanguage-link interwiki-fj mw-list-item"><a href="https://fj.wikipedia.org/wiki/Iwasewase" title="Iwasewase – Fijian" lang="fj" hreflang="fj" data-title="Iwasewase" data-language-autonym="Na Vosa Vakaviti" data-language-local-name="Fijian" class="interlanguage-link-target"><span>Na Vosa Vakaviti</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Oppervlakte" title="Oppervlakte – Dutch" lang="nl" hreflang="nl" data-title="Oppervlakte" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-nds-nl mw-list-item"><a href="https://nds-nl.wikipedia.org/wiki/Oppervlakte" title="Oppervlakte – Low Saxon" lang="nds-NL" hreflang="nds-NL" data-title="Oppervlakte" data-language-autonym="Nedersaksies" data-language-local-name="Low Saxon" class="interlanguage-link-target"><span>Nedersaksies</span></a></li><li class="interlanguage-link interwiki-ne mw-list-item"><a href="https://ne.wikipedia.org/wiki/%E0%A4%95%E0%A5%8D%E0%A4%B7%E0%A5%87%E0%A4%A4%E0%A5%8D%E0%A4%B0%E0%A4%AB%E0%A4%B2" title="क्षेत्रफल – Nepali" lang="ne" hreflang="ne" data-title="क्षेत्रफल" data-language-autonym="नेपाली" data-language-local-name="Nepali" class="interlanguage-link-target"><span>नेपाली</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E9%9D%A2%E7%A9%8D" title="面積 – Japanese" lang="ja" hreflang="ja" data-title="面積" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-ce mw-list-item"><a href="https://ce.wikipedia.org/wiki/%D0%9C%D0%B0%D0%B9%D0%B4%D0%B0" title="Майда – Chechen" lang="ce" hreflang="ce" data-title="Майда" data-language-autonym="Нохчийн" data-language-local-name="Chechen" class="interlanguage-link-target"><span>Нохчийн</span></a></li><li class="interlanguage-link interwiki-frr mw-list-item"><a href="https://frr.wikipedia.org/wiki/Areaal_(Miat)" title="Areaal (Miat) – Northern Frisian" lang="frr" hreflang="frr" data-title="Areaal (Miat)" data-language-autonym="Nordfriisk" data-language-local-name="Northern Frisian" class="interlanguage-link-target"><span>Nordfriisk</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Areal" title="Areal – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="Areal" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-nn mw-list-item"><a href="https://nn.wikipedia.org/wiki/Flatevidd" title="Flatevidd – Norwegian Nynorsk" lang="nn" hreflang="nn" data-title="Flatevidd" data-language-autonym="Norsk nynorsk" data-language-local-name="Norwegian Nynorsk" class="interlanguage-link-target"><span>Norsk nynorsk</span></a></li><li class="interlanguage-link interwiki-oc mw-list-item"><a href="https://oc.wikipedia.org/wiki/Aira" title="Aira – Occitan" lang="oc" hreflang="oc" data-title="Aira" data-language-autonym="Occitan" data-language-local-name="Occitan" class="interlanguage-link-target"><span>Occitan</span></a></li><li class="interlanguage-link interwiki-mhr mw-list-item"><a href="https://mhr.wikipedia.org/wiki/%D0%9A%D1%83%D0%BC%D0%B4%D1%8B%D0%BA" title="Кумдык – Eastern Mari" lang="mhr" hreflang="mhr" data-title="Кумдык" data-language-autonym="Олык марий" data-language-local-name="Eastern Mari" class="interlanguage-link-target"><span>Олык марий</span></a></li><li class="interlanguage-link interwiki-uz mw-list-item"><a href="https://uz.wikipedia.org/wiki/Yuza" title="Yuza – Uzbek" lang="uz" hreflang="uz" data-title="Yuza" data-language-autonym="Oʻzbekcha / ўзбекча" data-language-local-name="Uzbek" class="interlanguage-link-target"><span>Oʻzbekcha / ўзбекча</span></a></li><li class="interlanguage-link interwiki-pa mw-list-item"><a href="https://pa.wikipedia.org/wiki/%E0%A8%96%E0%A9%87%E0%A8%A4%E0%A8%B0%E0%A8%AB%E0%A8%B2" title="ਖੇਤਰਫਲ – Punjabi" lang="pa" hreflang="pa" data-title="ਖੇਤਰਫਲ" data-language-autonym="ਪੰਜਾਬੀ" data-language-local-name="Punjabi" class="interlanguage-link-target"><span>ਪੰਜਾਬੀ</span></a></li><li class="interlanguage-link interwiki-pfl mw-list-item"><a href="https://pfl.wikipedia.org/wiki/Fl%C3%A4che" title="Fläche – Palatine German" lang="pfl" hreflang="pfl" data-title="Fläche" data-language-autonym="Pälzisch" data-language-local-name="Palatine German" class="interlanguage-link-target"><span>Pälzisch</span></a></li><li class="interlanguage-link interwiki-pnb mw-list-item"><a href="https://pnb.wikipedia.org/wiki/%D8%B1%D9%82%D8%A8%DB%81" title="رقبہ – Western Punjabi" lang="pnb" hreflang="pnb" data-title="رقبہ" data-language-autonym="پنجابی" data-language-local-name="Western Punjabi" class="interlanguage-link-target"><span>پنجابی</span></a></li><li class="interlanguage-link interwiki-jam mw-list-item"><a href="https://jam.wikipedia.org/wiki/Ieria" title="Ieria – Jamaican Creole English" lang="jam" hreflang="jam" data-title="Ieria" data-language-autonym="Patois" data-language-local-name="Jamaican Creole English" class="interlanguage-link-target"><span>Patois</span></a></li><li class="interlanguage-link interwiki-km mw-list-item"><a href="https://km.wikipedia.org/wiki/%E1%9E%80%E1%9F%92%E1%9E%9A%E1%9E%9B%E1%9E%B6%E1%9E%95%E1%9F%92%E1%9E%91%E1%9F%83" title="ក្រលាផ្ទៃ – Khmer" lang="km" hreflang="km" data-title="ក្រលាផ្ទៃ" data-language-autonym="ភាសាខ្មែរ" data-language-local-name="Khmer" class="interlanguage-link-target"><span>ភាសាខ្មែរ</span></a></li><li class="interlanguage-link interwiki-nds mw-list-item"><a href="https://nds.wikipedia.org/wiki/Flach" title="Flach – Low German" lang="nds" hreflang="nds" data-title="Flach" data-language-autonym="Plattdüütsch" data-language-local-name="Low German" class="interlanguage-link-target"><span>Plattdüütsch</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Pole_powierzchni" title="Pole powierzchni – Polish" lang="pl" hreflang="pl" data-title="Pole powierzchni" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/%C3%81rea" title="Área – Portuguese" lang="pt" hreflang="pt" data-title="Área" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Arie" title="Arie – Romanian" lang="ro" hreflang="ro" data-title="Arie" data-language-autonym="Română" data-language-local-name="Romanian" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-qu mw-list-item"><a href="https://qu.wikipedia.org/wiki/Hallka_k%27iti_k%27anchar" title="Hallka k&#039;iti k&#039;anchar – Quechua" lang="qu" hreflang="qu" data-title="Hallka k&#039;iti k&#039;anchar" data-language-autonym="Runa Simi" data-language-local-name="Quechua" class="interlanguage-link-target"><span>Runa Simi</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%9F%D0%BB%D0%BE%D1%89%D0%B0%D0%B4%D1%8C" title="Площадь – Russian" lang="ru" hreflang="ru" data-title="Площадь" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-sah mw-list-item"><a href="https://sah.wikipedia.org/wiki/%D0%98%D1%8D%D0%BD" title="Иэн – Yakut" lang="sah" hreflang="sah" data-title="Иэн" data-language-autonym="Саха тыла" data-language-local-name="Yakut" class="interlanguage-link-target"><span>Саха тыла</span></a></li><li class="interlanguage-link interwiki-sa mw-list-item"><a href="https://sa.wikipedia.org/wiki/%E0%A4%95%E0%A5%8D%E0%A4%B7%E0%A5%87%E0%A4%A4%E0%A5%8D%E0%A4%B0%E0%A4%AB%E0%A4%B2%E0%A4%AE%E0%A5%8D" title="क्षेत्रफलम् – Sanskrit" lang="sa" hreflang="sa" data-title="क्षेत्रफलम्" data-language-autonym="संस्कृतम्" data-language-local-name="Sanskrit" class="interlanguage-link-target"><span>संस्कृतम्</span></a></li><li class="interlanguage-link interwiki-sco mw-list-item"><a href="https://sco.wikipedia.org/wiki/Area" title="Area – Scots" lang="sco" hreflang="sco" data-title="Area" data-language-autonym="Scots" data-language-local-name="Scots" class="interlanguage-link-target"><span>Scots</span></a></li><li class="interlanguage-link interwiki-sq mw-list-item"><a href="https://sq.wikipedia.org/wiki/Sip%C3%ABrfaqja" title="Sipërfaqja – Albanian" lang="sq" hreflang="sq" data-title="Sipërfaqja" data-language-autonym="Shqip" data-language-local-name="Albanian" class="interlanguage-link-target"><span>Shqip</span></a></li><li class="interlanguage-link interwiki-scn mw-list-item"><a href="https://scn.wikipedia.org/wiki/%C3%80ria_(supirfici)" title="Ària (supirfici) – Sicilian" lang="scn" hreflang="scn" data-title="Ària (supirfici)" data-language-autonym="Sicilianu" data-language-local-name="Sicilian" class="interlanguage-link-target"><span>Sicilianu</span></a></li><li class="interlanguage-link interwiki-simple mw-list-item"><a href="https://simple.wikipedia.org/wiki/Area" title="Area – Simple English" lang="en-simple" hreflang="en-simple" data-title="Area" data-language-autonym="Simple English" data-language-local-name="Simple English" class="interlanguage-link-target"><span>Simple English</span></a></li><li class="interlanguage-link interwiki-sd mw-list-item"><a href="https://sd.wikipedia.org/wiki/%D8%A7%D9%8A%D8%B1%D8%A7%D8%B6%D9%8A" title="ايراضي – Sindhi" lang="sd" hreflang="sd" data-title="ايراضي" data-language-autonym="سنڌي" data-language-local-name="Sindhi" class="interlanguage-link-target"><span>سنڌي</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/Plocha_(%C3%BAtvar)" title="Plocha (útvar) – Slovak" lang="sk" hreflang="sk" data-title="Plocha (útvar)" data-language-autonym="Slovenčina" data-language-local-name="Slovak" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-sl mw-list-item"><a href="https://sl.wikipedia.org/wiki/Povr%C5%A1ina" title="Površina – Slovenian" lang="sl" hreflang="sl" data-title="Površina" data-language-autonym="Slovenščina" data-language-local-name="Slovenian" class="interlanguage-link-target"><span>Slovenščina</span></a></li><li class="interlanguage-link interwiki-cu mw-list-item"><a href="https://cu.wikipedia.org/wiki/%D0%9F%D1%80%D0%BE%D1%81%D1%82%D1%80%D0%B0%D0%BD%D0%B8%D1%A5" title="Пространиѥ – Church Slavic" lang="cu" hreflang="cu" data-title="Пространиѥ" data-language-autonym="Словѣньскъ / ⰔⰎⰑⰂⰡⰐⰠⰔⰍⰟ" data-language-local-name="Church Slavic" class="interlanguage-link-target"><span>Словѣньскъ / ⰔⰎⰑⰂⰡⰐⰠⰔⰍⰟ</span></a></li><li class="interlanguage-link interwiki-szl mw-list-item"><a href="https://szl.wikipedia.org/wiki/Plac_rozlygowa%C5%84o" title="Plac rozlygowańo – Silesian" lang="szl" hreflang="szl" data-title="Plac rozlygowańo" data-language-autonym="Ślůnski" data-language-local-name="Silesian" class="interlanguage-link-target"><span>Ślůnski</span></a></li><li class="interlanguage-link interwiki-so mw-list-item"><a href="https://so.wikipedia.org/wiki/Bed" title="Bed – Somali" lang="so" hreflang="so" data-title="Bed" data-language-autonym="Soomaaliga" data-language-local-name="Somali" class="interlanguage-link-target"><span>Soomaaliga</span></a></li><li class="interlanguage-link interwiki-ckb mw-list-item"><a href="https://ckb.wikipedia.org/wiki/%DA%95%D9%88%D9%88%D8%A8%DB%95%D8%B1" title="ڕووبەر – Central Kurdish" lang="ckb" hreflang="ckb" data-title="ڕووبەر" data-language-autonym="کوردی" data-language-local-name="Central Kurdish" class="interlanguage-link-target"><span>کوردی</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/%D0%9F%D0%BE%D0%B2%D1%80%D1%88%D0%B8%D0%BD%D0%B0" title="Површина – Serbian" lang="sr" hreflang="sr" data-title="Површина" data-language-autonym="Српски / srpski" data-language-local-name="Serbian" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-sh mw-list-item"><a href="https://sh.wikipedia.org/wiki/Povr%C5%A1ina" title="Površina – Serbo-Croatian" lang="sh" hreflang="sh" data-title="Površina" data-language-autonym="Srpskohrvatski / српскохрватски" data-language-local-name="Serbo-Croatian" class="interlanguage-link-target"><span>Srpskohrvatski / српскохрватски</span></a></li><li class="interlanguage-link interwiki-su mw-list-item"><a href="https://su.wikipedia.org/wiki/Ar%C3%A9a" title="Aréa – Sundanese" lang="su" hreflang="su" data-title="Aréa" data-language-autonym="Sunda" data-language-local-name="Sundanese" class="interlanguage-link-target"><span>Sunda</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/Pinta-ala" title="Pinta-ala – Finnish" lang="fi" hreflang="fi" data-title="Pinta-ala" data-language-autonym="Suomi" data-language-local-name="Finnish" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Area" title="Area – Swedish" lang="sv" hreflang="sv" data-title="Area" data-language-autonym="Svenska" data-language-local-name="Swedish" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-tl mw-list-item"><a href="https://tl.wikipedia.org/wiki/Sukat" title="Sukat – Tagalog" lang="tl" hreflang="tl" data-title="Sukat" data-language-autonym="Tagalog" data-language-local-name="Tagalog" class="interlanguage-link-target"><span>Tagalog</span></a></li><li class="interlanguage-link interwiki-ta mw-list-item"><a href="https://ta.wikipedia.org/wiki/%E0%AE%AA%E0%AE%B0%E0%AE%AA%E0%AF%8D%E0%AE%AA%E0%AE%B3%E0%AE%B5%E0%AF%81" title="பரப்பளவு – Tamil" lang="ta" hreflang="ta" data-title="பரப்பளவு" data-language-autonym="தமிழ்" data-language-local-name="Tamil" class="interlanguage-link-target"><span>தமிழ்</span></a></li><li class="interlanguage-link interwiki-kab mw-list-item"><a href="https://kab.wikipedia.org/wiki/Tajumma" title="Tajumma – Kabyle" lang="kab" hreflang="kab" data-title="Tajumma" data-language-autonym="Taqbaylit" data-language-local-name="Kabyle" class="interlanguage-link-target"><span>Taqbaylit</span></a></li><li class="interlanguage-link interwiki-tt mw-list-item"><a href="https://tt.wikipedia.org/wiki/M%C3%A4ydan" title="Mäydan – Tatar" lang="tt" hreflang="tt" data-title="Mäydan" data-language-autonym="Татарча / tatarça" data-language-local-name="Tatar" class="interlanguage-link-target"><span>Татарча / tatarça</span></a></li><li class="interlanguage-link interwiki-te mw-list-item"><a href="https://te.wikipedia.org/wiki/%E0%B0%B5%E0%B0%BF%E0%B0%B8%E0%B1%8D%E0%B0%A4%E0%B1%80%E0%B0%B0%E0%B1%8D%E0%B0%A3%E0%B0%82" title="విస్తీర్ణం – Telugu" lang="te" hreflang="te" data-title="విస్తీర్ణం" data-language-autonym="తెలుగు" data-language-local-name="Telugu" class="interlanguage-link-target"><span>తెలుగు</span></a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B8%9E%E0%B8%B7%E0%B9%89%E0%B8%99%E0%B8%97%E0%B8%B5%E0%B9%88" title="พื้นที่ – Thai" lang="th" hreflang="th" data-title="พื้นที่" data-language-autonym="ไทย" data-language-local-name="Thai" class="interlanguage-link-target"><span>ไทย</span></a></li><li class="interlanguage-link interwiki-ti mw-list-item"><a href="https://ti.wikipedia.org/wiki/%E1%8C%BD%E1%8D%8D%E1%88%93%E1%89%B5_%E1%88%98%E1%88%AC%E1%89%B5" title="ጽፍሓት መሬት – Tigrinya" lang="ti" hreflang="ti" data-title="ጽፍሓት መሬት" data-language-autonym="ትግርኛ" data-language-local-name="Tigrinya" class="interlanguage-link-target"><span>ትግርኛ</span></a></li><li class="interlanguage-link interwiki-tg mw-list-item"><a href="https://tg.wikipedia.org/wiki/%D0%9C%D0%B0%D1%81%D0%BE%D2%B3%D0%B0%D1%82" title="Масоҳат – Tajik" lang="tg" hreflang="tg" data-title="Масоҳат" data-language-autonym="Тоҷикӣ" data-language-local-name="Tajik" class="interlanguage-link-target"><span>Тоҷикӣ</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/Alan" title="Alan – Turkish" lang="tr" hreflang="tr" data-title="Alan" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%9F%D0%BB%D0%BE%D1%89%D0%B0" title="Площа – Ukrainian" lang="uk" hreflang="uk" data-title="Площа" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-ur mw-list-item"><a href="https://ur.wikipedia.org/wiki/%D8%B1%D9%82%D8%A8%DB%81" title="رقبہ – Urdu" lang="ur" hreflang="ur" data-title="رقبہ" data-language-autonym="اردو" data-language-local-name="Urdu" class="interlanguage-link-target"><span>اردو</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/Di%E1%BB%87n_t%C3%ADch" title="Diện tích – Vietnamese" lang="vi" hreflang="vi" data-title="Diện tích" data-language-autonym="Tiếng Việt" data-language-local-name="Vietnamese" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-fiu-vro mw-list-item"><a href="https://fiu-vro.wikipedia.org/wiki/Pindala" title="Pindala – Võro" lang="vro" hreflang="vro" data-title="Pindala" data-language-autonym="Võro" data-language-local-name="Võro" class="interlanguage-link-target"><span>Võro</span></a></li><li class="interlanguage-link interwiki-wa mw-list-item"><a href="https://wa.wikipedia.org/wiki/Sitind%C3%AAye" title="Sitindêye – Walloon" lang="wa" hreflang="wa" data-title="Sitindêye" data-language-autonym="Walon" data-language-local-name="Walloon" class="interlanguage-link-target"><span>Walon</span></a></li><li class="interlanguage-link interwiki-vls mw-list-item"><a href="https://vls.wikipedia.org/wiki/Ippervlak" title="Ippervlak – West Flemish" lang="vls" hreflang="vls" data-title="Ippervlak" data-language-autonym="West-Vlams" data-language-local-name="West Flemish" class="interlanguage-link-target"><span>West-Vlams</span></a></li><li class="interlanguage-link interwiki-war mw-list-item"><a href="https://war.wikipedia.org/wiki/Kahaluag" title="Kahaluag – Waray" lang="war" hreflang="war" data-title="Kahaluag" data-language-autonym="Winaray" data-language-local-name="Waray" class="interlanguage-link-target"><span>Winaray</span></a></li><li class="interlanguage-link interwiki-wo mw-list-item"><a href="https://wo.wikipedia.org/wiki/Yaatuwaay" title="Yaatuwaay – Wolof" lang="wo" hreflang="wo" data-title="Yaatuwaay" data-language-autonym="Wolof" data-language-local-name="Wolof" class="interlanguage-link-target"><span>Wolof</span></a></li><li class="interlanguage-link interwiki-wuu mw-list-item"><a href="https://wuu.wikipedia.org/wiki/%E9%9D%A2%E7%A7%AF" title="面积 – Wu" lang="wuu" hreflang="wuu" data-title="面积" data-language-autonym="吴语" data-language-local-name="Wu" class="interlanguage-link-target"><span>吴语</span></a></li><li class="interlanguage-link interwiki-yi mw-list-item"><a href="https://yi.wikipedia.org/wiki/%D7%A9%D7%98%D7%97" title="שטח – Yiddish" lang="yi" hreflang="yi" data-title="שטח" data-language-autonym="ייִדיש" data-language-local-name="Yiddish" class="interlanguage-link-target"><span>ייִדיש</span></a></li><li class="interlanguage-link interwiki-yo mw-list-item"><a href="https://yo.wikipedia.org/wiki/%C3%80%C3%A0l%C3%A0" title="Ààlà – Yoruba" lang="yo" hreflang="yo" data-title="Ààlà" data-language-autonym="Yorùbá" data-language-local-name="Yoruba" class="interlanguage-link-target"><span>Yorùbá</span></a></li><li class="interlanguage-link interwiki-zh-yue mw-list-item"><a href="https://zh-yue.wikipedia.org/wiki/%E9%9D%A2%E7%A9%8D" title="面積 – Cantonese" lang="yue" hreflang="yue" data-title="面積" data-language-autonym="粵語" data-language-local-name="Cantonese" class="interlanguage-link-target"><span>粵語</span></a></li><li class="interlanguage-link interwiki-diq mw-list-item"><a href="https://diq.wikipedia.org/wiki/Erd" title="Erd – Zazaki" lang="diq" hreflang="diq" data-title="Erd" data-language-autonym="Zazaki" data-language-local-name="Zazaki" class="interlanguage-link-target"><span>Zazaki</span></a></li><li class="interlanguage-link interwiki-zea mw-list-item"><a href="https://zea.wikipedia.org/wiki/Oppervlak" title="Oppervlak – Zeelandic" lang="zea" hreflang="zea" data-title="Oppervlak" data-language-autonym="Zeêuws" data-language-local-name="Zeelandic" class="interlanguage-link-target"><span>Zeêuws</span></a></li><li class="interlanguage-link interwiki-bat-smg mw-list-item"><a href="https://bat-smg.wikipedia.org/wiki/Pluots" title="Pluots – Samogitian" lang="sgs" hreflang="sgs" data-title="Pluots" data-language-autonym="Žemaitėška" data-language-local-name="Samogitian" class="interlanguage-link-target"><span>Žemaitėška</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E9%9D%A2%E7%A7%AF" title="面积 – Chinese" lang="zh" hreflang="zh" data-title="面积" data-language-autonym="中文" data-language-local-name="Chinese" class="interlanguage-link-target"><span>中文</span></a></li><li class="interlanguage-link interwiki-btm mw-list-item"><a href="https://btm.wikipedia.org/wiki/Bolak" title="Bolak – Batak Mandailing" lang="btm" hreflang="btm" data-title="Bolak" data-language-autonym="Batak Mandailing" data-language-local-name="Batak Mandailing" class="interlanguage-link-target"><span>Batak Mandailing</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit wb-langlinks-link"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q11500#sitelinks-wikipedia" title="Edit interlanguage links" class="wbc-editpage">Edit links</a></span></div> </div> </div> </div> </header> <div class="vector-page-toolbar"> <div class="vector-page-toolbar-container"> <div id="left-navigation"> <nav aria-label="Namespaces"> <div id="p-associated-pages" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-associated-pages" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-nstab-main" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Area" title="View the content page [c]" accesskey="c"><span>Article</span></a></li><li id="ca-talk" class="vector-tab-noicon mw-list-item"><a href="/wiki/Talk:Area" rel="discussion" title="Discuss improvements to the content page [t]" accesskey="t"><span>Talk</span></a></li> </ul> </div> </div> <div id="vector-variants-dropdown" class="vector-dropdown emptyPortlet" > <input type="checkbox" id="vector-variants-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-variants-dropdown" class="vector-dropdown-checkbox " aria-label="Change language variant" > <label id="vector-variants-dropdown-label" for="vector-variants-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">English</span> </label> <div class="vector-dropdown-content"> <div id="p-variants" class="vector-menu mw-portlet mw-portlet-variants emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> </div> </div> </nav> </div> <div id="right-navigation" class="vector-collapsible"> <nav aria-label="Views"> <div id="p-views" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-views" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-view" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Area"><span>Read</span></a></li><li id="ca-edit" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Area&amp;action=edit" title="Edit this page [e]" accesskey="e"><span>Edit</span></a></li><li id="ca-history" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=Area&amp;action=history" title="Past revisions of this page [h]" accesskey="h"><span>View history</span></a></li> </ul> </div> </div> </nav> <nav class="vector-page-tools-landmark" aria-label="Page tools"> <div id="vector-page-tools-dropdown" class="vector-dropdown vector-page-tools-dropdown" > <input type="checkbox" id="vector-page-tools-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-tools-dropdown" class="vector-dropdown-checkbox " aria-label="Tools" > <label id="vector-page-tools-dropdown-label" for="vector-page-tools-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">Tools</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-tools-unpinned-container" class="vector-unpinned-container"> <div id="vector-page-tools" class="vector-page-tools vector-pinnable-element"> <div class="vector-pinnable-header vector-page-tools-pinnable-header vector-pinnable-header-unpinned" data-feature-name="page-tools-pinned" data-pinnable-element-id="vector-page-tools" data-pinned-container-id="vector-page-tools-pinned-container" data-unpinned-container-id="vector-page-tools-unpinned-container" > <div class="vector-pinnable-header-label">Tools</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-page-tools.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-page-tools.unpin">hide</button> </div> <div id="p-cactions" class="vector-menu mw-portlet mw-portlet-cactions emptyPortlet vector-has-collapsible-items" title="More options" > <div class="vector-menu-heading"> Actions </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-more-view" class="selected vector-more-collapsible-item mw-list-item"><a href="/wiki/Area"><span>Read</span></a></li><li id="ca-more-edit" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Area&amp;action=edit" title="Edit this page [e]" accesskey="e"><span>Edit</span></a></li><li id="ca-more-history" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=Area&amp;action=history"><span>View history</span></a></li> </ul> </div> </div> <div id="p-tb" class="vector-menu mw-portlet mw-portlet-tb" > <div class="vector-menu-heading"> General </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="t-whatlinkshere" class="mw-list-item"><a href="/wiki/Special:WhatLinksHere/Area" title="List of all English Wikipedia pages containing links to this page [j]" accesskey="j"><span>What links here</span></a></li><li id="t-recentchangeslinked" class="mw-list-item"><a href="/wiki/Special:RecentChangesLinked/Area" rel="nofollow" title="Recent changes in pages linked from this page [k]" accesskey="k"><span>Related changes</span></a></li><li id="t-upload" class="mw-list-item"><a href="/wiki/Wikipedia:File_Upload_Wizard" title="Upload files [u]" accesskey="u"><span>Upload file</span></a></li><li id="t-specialpages" class="mw-list-item"><a href="/wiki/Special:SpecialPages" title="A list of all special pages [q]" accesskey="q"><span>Special pages</span></a></li><li id="t-permalink" class="mw-list-item"><a href="/w/index.php?title=Area&amp;oldid=1255146594" title="Permanent link to this revision of this page"><span>Permanent link</span></a></li><li id="t-info" class="mw-list-item"><a href="/w/index.php?title=Area&amp;action=info" title="More information about this page"><span>Page information</span></a></li><li id="t-cite" class="mw-list-item"><a href="/w/index.php?title=Special:CiteThisPage&amp;page=Area&amp;id=1255146594&amp;wpFormIdentifier=titleform" title="Information on how to cite this page"><span>Cite this page</span></a></li><li id="t-urlshortener" class="mw-list-item"><a href="/w/index.php?title=Special:UrlShortener&amp;url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FArea"><span>Get shortened URL</span></a></li><li id="t-urlshortener-qrcode" class="mw-list-item"><a href="/w/index.php?title=Special:QrCode&amp;url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FArea"><span>Download QR code</span></a></li> </ul> </div> </div> <div id="p-coll-print_export" class="vector-menu mw-portlet mw-portlet-coll-print_export" > <div class="vector-menu-heading"> Print/export </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="coll-download-as-rl" class="mw-list-item"><a href="/w/index.php?title=Special:DownloadAsPdf&amp;page=Area&amp;action=show-download-screen" title="Download this page as a PDF file"><span>Download as PDF</span></a></li><li id="t-print" class="mw-list-item"><a href="/w/index.php?title=Area&amp;printable=yes" title="Printable version of this page [p]" accesskey="p"><span>Printable version</span></a></li> </ul> </div> </div> <div id="p-wikibase-otherprojects" class="vector-menu mw-portlet mw-portlet-wikibase-otherprojects" > <div class="vector-menu-heading"> In other projects </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="wb-otherproject-link wb-otherproject-commons mw-list-item"><a href="https://commons.wikimedia.org/wiki/Category:Area" hreflang="en"><span>Wikimedia Commons</span></a></li><li id="t-wikibase" class="wb-otherproject-link wb-otherproject-wikibase-dataitem mw-list-item"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q11500" title="Structured data on this page hosted by Wikidata [g]" accesskey="g"><span>Wikidata item</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> </div> </div> </div> <div class="vector-column-end"> <div class="vector-sticky-pinned-container"> <nav class="vector-page-tools-landmark" aria-label="Page tools"> <div id="vector-page-tools-pinned-container" class="vector-pinned-container"> </div> </nav> <nav class="vector-appearance-landmark" aria-label="Appearance"> <div id="vector-appearance-pinned-container" class="vector-pinned-container"> <div id="vector-appearance" class="vector-appearance vector-pinnable-element"> <div class="vector-pinnable-header vector-appearance-pinnable-header vector-pinnable-header-pinned" data-feature-name="appearance-pinned" data-pinnable-element-id="vector-appearance" data-pinned-container-id="vector-appearance-pinned-container" data-unpinned-container-id="vector-appearance-unpinned-container" > <div class="vector-pinnable-header-label">Appearance</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-appearance.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-appearance.unpin">hide</button> </div> </div> </div> </nav> </div> </div> <div id="bodyContent" class="vector-body" aria-labelledby="firstHeading" data-mw-ve-target-container> <div class="vector-body-before-content"> <div class="mw-indicators"> </div> <div id="siteSub" class="noprint">From Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"><span class="mw-redirectedfrom">(Redirected from <a href="/w/index.php?title=Areas&amp;redirect=no" class="mw-redirect" title="Areas">Areas</a>)</span></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Size of a two-dimensional surface</div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">This article is about the geometric quantity. For other uses, see <a href="/wiki/Area_(disambiguation)" class="mw-disambig" title="Area (disambiguation)">Area (disambiguation)</a>.</div> <p class="mw-empty-elt"> </p> <style data-mw-deduplicate="TemplateStyles:r1257001546">.mw-parser-output .infobox-subbox{padding:0;border:none;margin:-3px;width:auto;min-width:100%;font-size:100%;clear:none;float:none;background-color:transparent}.mw-parser-output .infobox-3cols-child{margin:auto}.mw-parser-output .infobox .navbar{font-size:100%}@media screen{html.skin-theme-clientpref-night .mw-parser-output .infobox-full-data:not(.notheme)>div:not(.notheme)[style]{background:#1f1f23!important;color:#f8f9fa}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .infobox-full-data:not(.notheme) div:not(.notheme){background:#1f1f23!important;color:#f8f9fa}}@media(min-width:640px){body.skin--responsive .mw-parser-output .infobox-table{display:table!important}body.skin--responsive .mw-parser-output .infobox-table>caption{display:table-caption!important}body.skin--responsive .mw-parser-output .infobox-table>tbody{display:table-row-group}body.skin--responsive .mw-parser-output .infobox-table tr{display:table-row!important}body.skin--responsive .mw-parser-output .infobox-table th,body.skin--responsive .mw-parser-output .infobox-table td{padding-left:inherit;padding-right:inherit}}</style><table class="infobox"><tbody><tr><th colspan="2" class="infobox-above">Area</th></tr><tr><td colspan="2" class="infobox-image"><span class="mw-default-size" typeof="mw:File/Frameless"><a href="/wiki/File:Squaring_the_circle.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/a/a7/Squaring_the_circle.svg/220px-Squaring_the_circle.svg.png" decoding="async" width="220" height="220" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/a7/Squaring_the_circle.svg/330px-Squaring_the_circle.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/a7/Squaring_the_circle.svg/440px-Squaring_the_circle.svg.png 2x" data-file-width="281" data-file-height="281" /></a></span><div class="infobox-caption">The areas of this square and this <a href="/wiki/Disk_(mathematics)" title="Disk (mathematics)">disk</a> are the same.</div></td></tr><tr><th scope="row" class="infobox-label"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Common symbols</div></th><td class="infobox-data"><i>A</i> or <i>S</i></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/SI_unit" class="mw-redirect" title="SI unit">SI&#160;unit</a></th><td class="infobox-data"><a href="/wiki/Square_metre" title="Square metre">Square metre</a> [m<sup>2</sup>]</td></tr><tr><th scope="row" class="infobox-label">In <a href="/wiki/SI_base_unit" title="SI base unit"><span class="wrap">SI&#160;base units</span></a></th><td class="infobox-data">1&#160;<a href="/wiki/Metre" title="Metre">m</a><sup>2</sup></td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Dimensional_analysis#Formulation" title="Dimensional analysis">Dimension</a></th><td class="infobox-data"><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\mathsf {L}}^{2}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msup> <mrow class="MJX-TeXAtom-ORD"> <mrow class="MJX-TeXAtom-ORD"> <mi mathvariant="sans-serif">L</mi> </mrow> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle {\mathsf {L}}^{2}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/e315c7dc801b08df18f46f1069d4ecbb7760be35" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:2.314ex; height:2.676ex;" alt="{\displaystyle {\mathsf {L}}^{2}}"></span></td></tr></tbody></table> <p><b>Area</b> is the <a href="/wiki/Measure_(mathematics)" title="Measure (mathematics)">measure</a> of a <a href="/wiki/Domain_(mathematical_analysis)" title="Domain (mathematical analysis)">region</a>'s size on a <a href="/wiki/Surface_(mathematics)" title="Surface (mathematics)">surface</a>. The area of a plane region or <i>plane area</i> refers to the area of a <a href="/wiki/Shape" title="Shape">shape</a> or <a href="/wiki/Planar_lamina" title="Planar lamina">planar lamina</a>, while <i><a href="/wiki/Surface_area" title="Surface area">surface area</a></i> refers to the area of an <a href="/wiki/Open_surface" class="mw-redirect" title="Open surface">open surface</a> or the <a href="/wiki/Boundary_(mathematics)" class="mw-redirect" title="Boundary (mathematics)">boundary</a> of a <a href="/wiki/Solid_geometry" title="Solid geometry">three-dimensional object</a>. Area can be understood as the amount of material with a given thickness that would be necessary to fashion a model of the shape, or the amount of <a href="/wiki/Paint" title="Paint">paint</a> necessary to cover the surface with a single coat.<sup id="cite_ref-MathWorld_1-0" class="reference"><a href="#cite_note-MathWorld-1"><span class="cite-bracket">&#91;</span>1<span class="cite-bracket">&#93;</span></a></sup> It is the two-dimensional analogue of the <a href="/wiki/Length" title="Length">length</a> of a <a href="/wiki/Plane_curve" title="Plane curve">curve</a> (a one-dimensional concept) or the <a href="/wiki/Volume" title="Volume">volume</a> of a solid (a three-dimensional concept). Two different regions may have the same area (as in <a href="/wiki/Squaring_the_circle" title="Squaring the circle">squaring the circle</a>); by <a href="/wiki/Synecdoche" title="Synecdoche">synecdoche</a>, "area" sometimes is used to refer to the region, as in a "<a href="/wiki/Polygonal_area" class="mw-redirect" title="Polygonal area">polygonal area</a>". </p><p>The area of a shape can be measured by comparing the shape to <a href="/wiki/Square" title="Square">squares</a> of a fixed size.<sup id="cite_ref-AF_2-0" class="reference"><a href="#cite_note-AF-2"><span class="cite-bracket">&#91;</span>2<span class="cite-bracket">&#93;</span></a></sup> In the <a href="/wiki/International_System_of_Units" title="International System of Units">International System of Units</a> (SI), the standard unit of area is the <a href="/wiki/Square_metre" title="Square metre">square metre</a> (written as m<sup>2</sup>), which is the area of a square whose sides are one <a href="/wiki/Metre" title="Metre">metre</a> long.<sup id="cite_ref-B_3-0" class="reference"><a href="#cite_note-B-3"><span class="cite-bracket">&#91;</span>3<span class="cite-bracket">&#93;</span></a></sup> A shape with an area of three square metres would have the same area as three such squares. In <a href="/wiki/Mathematics" title="Mathematics">mathematics</a>, the <a href="/wiki/Unit_square" title="Unit square">unit square</a> is defined to have area one, and the area of any other shape or surface is a <a href="/wiki/Dimensionless_quantity" title="Dimensionless quantity">dimensionless</a> <a href="/wiki/Real_number" title="Real number">real number</a>. </p><p>There are several well-known <a href="/wiki/Formula" title="Formula">formulas</a> for the areas of simple shapes such as <a href="/wiki/Triangle" title="Triangle">triangles</a>, <a href="/wiki/Rectangle" title="Rectangle">rectangles</a>, and <a href="/wiki/Circle" title="Circle">circles</a>. Using these formulas, the area of any <a href="/wiki/Polygon" title="Polygon">polygon</a> can be found by <a href="/wiki/Polygon_triangulation" title="Polygon triangulation">dividing the polygon into triangles</a>.<sup id="cite_ref-bkos_4-0" class="reference"><a href="#cite_note-bkos-4"><span class="cite-bracket">&#91;</span>4<span class="cite-bracket">&#93;</span></a></sup> For shapes with curved boundary, <a href="/wiki/Calculus" title="Calculus">calculus</a> is usually required to compute the area. Indeed, the problem of determining the area of plane figures was a major motivation for the <a href="/wiki/History_of_calculus" title="History of calculus">historical development of calculus</a>.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">&#91;</span>5<span class="cite-bracket">&#93;</span></a></sup> </p><p>For a solid shape such as a <a href="/wiki/Sphere" title="Sphere">sphere</a>, cone, or cylinder, the area of its boundary surface is called the <a href="/wiki/Surface_area" title="Surface area">surface area</a>.<sup id="cite_ref-MathWorld_1-1" class="reference"><a href="#cite_note-MathWorld-1"><span class="cite-bracket">&#91;</span>1<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-MathWorldSurfaceArea_6-0" class="reference"><a href="#cite_note-MathWorldSurfaceArea-6"><span class="cite-bracket">&#91;</span>6<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">&#91;</span>7<span class="cite-bracket">&#93;</span></a></sup> Formulas for the surface areas of simple shapes were computed by the <a href="/wiki/Greek_mathematics" title="Greek mathematics">ancient Greeks</a>, but computing the surface area of a more complicated shape usually requires <a href="/wiki/Multivariable_calculus" title="Multivariable calculus">multivariable calculus</a>. </p><p>Area plays an important role in modern mathematics. In addition to its obvious importance in <a href="/wiki/Geometry" title="Geometry">geometry</a> and calculus, area is related to the definition of <a href="/wiki/Determinant" title="Determinant">determinants</a> in <a href="/wiki/Linear_algebra" title="Linear algebra">linear algebra</a>, and is a basic property of surfaces in <a href="/wiki/Differential_geometry" title="Differential geometry">differential geometry</a>.<sup id="cite_ref-doCarmo_8-0" class="reference"><a href="#cite_note-doCarmo-8"><span class="cite-bracket">&#91;</span>8<span class="cite-bracket">&#93;</span></a></sup> In <a href="/wiki/Analysis" title="Analysis">analysis</a>, the area of a subset of the plane is defined using <a href="/wiki/Lebesgue_measure" title="Lebesgue measure">Lebesgue measure</a>,<sup id="cite_ref-Rudin_9-0" class="reference"><a href="#cite_note-Rudin-9"><span class="cite-bracket">&#91;</span>9<span class="cite-bracket">&#93;</span></a></sup> though not every subset is measurable if one supposes the axiom of choice.<sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">&#91;</span>10<span class="cite-bracket">&#93;</span></a></sup> In general, area in higher mathematics is seen as a special case of volume for two-dimensional regions.<sup id="cite_ref-MathWorld_1-2" class="reference"><a href="#cite_note-MathWorld-1"><span class="cite-bracket">&#91;</span>1<span class="cite-bracket">&#93;</span></a></sup> </p><p>Area can be defined through the use of axioms, defining it as a function of a collection of certain plane figures to the set of real numbers. It can be proved that such a function exists. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Formal_definition">Formal definition</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=1" title="Edit section: Formal definition"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Jordan_measure" class="mw-redirect" title="Jordan measure">Jordan measure</a></div> <p>An approach to defining what is meant by "area" is through <a href="/wiki/Axiom" title="Axiom">axioms</a>. "Area" can be defined as a function from a collection M of a special kinds of plane figures (termed measurable sets) to the set of real numbers, which satisfies the following properties:<sup id="cite_ref-Apostol_11-0" class="reference"><a href="#cite_note-Apostol-11"><span class="cite-bracket">&#91;</span>11<span class="cite-bracket">&#93;</span></a></sup> </p> <ul><li>For all <i>S</i> in <i>M</i>, <span class="nowrap"><i>a</i>(<i>S</i>) ≥ 0</span>.</li> <li>If <i>S</i> and <i>T</i> are in <i>M</i> then so are <span class="nowrap"><i>S</i> ∪ <i>T</i></span> and <span class="nowrap"><i>S</i> ∩ <i>T</i></span>, and also <span class="nowrap"><i>a</i>(<i>S</i>∪<i>T</i>) = <i>a</i>(<i>S</i>) + <i>a</i>(<i>T</i>) − <i>a</i>(<i>S</i> ∩ <i>T</i>)</span>.</li> <li>If <i>S</i> and <i>T</i> are in <i>M</i> with <span class="nowrap"><i>S</i> ⊆ <i>T</i></span> then <span class="nowrap"><i>T</i> − <i>S</i></span> is in <i>M</i> and <span class="nowrap"><i>a</i>(<i>T</i>−<i>S</i>) = <i>a</i>(<i>T</i>) − <i>a</i>(<i>S</i>)</span>.</li> <li>If a set <i>S</i> is in <i>M</i> and <i>S</i> is congruent to <i>T</i> then <i>T</i> is also in <i>M</i> and <span class="nowrap"><i>a</i>(<i>S</i>) = <i>a</i>(<i>T</i>)</span>.</li> <li>Every rectangle <i>R</i> is in <i>M</i>. If the rectangle has length <i>h</i> and breadth <i>k</i> then <span class="nowrap"><i>a</i>(<i>R</i>) = <i>hk</i></span>.</li> <li>Let <i>Q</i> be a set enclosed between two step regions <i>S</i> and <i>T</i>. A step region is formed from a finite union of adjacent rectangles resting on a common base, i.e. <span class="nowrap"><i>S</i> ⊆ <i>Q</i> ⊆ <i>T</i></span>. If there is a unique number <i>c</i> such that <span class="nowrap"><i>a</i>(<i>S</i>) ≤ c ≤ <i>a</i>(<i>T</i>)</span> for all such step regions <i>S</i> and <i>T</i>, then <span class="nowrap"><i>a</i>(<i>Q</i>) = <i>c</i></span>.</li></ul> <p>It can be proved that such an area function actually exists.<sup id="cite_ref-Moise_12-0" class="reference"><a href="#cite_note-Moise-12"><span class="cite-bracket">&#91;</span>12<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Units">Units</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=2" title="Edit section: Units"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:SquareMeterQuadrat.JPG" class="mw-file-description"><img alt="A square made of PVC pipe on grass" src="//upload.wikimedia.org/wikipedia/commons/thumb/e/ef/SquareMeterQuadrat.JPG/220px-SquareMeterQuadrat.JPG" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/ef/SquareMeterQuadrat.JPG/330px-SquareMeterQuadrat.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/ef/SquareMeterQuadrat.JPG/440px-SquareMeterQuadrat.JPG 2x" data-file-width="2048" data-file-height="1536" /></a><figcaption>A square metre <a href="/wiki/Quadrat" title="Quadrat">quadrat</a> made of PVC pipe</figcaption></figure> <p>Every <a href="/wiki/Unit_of_length" title="Unit of length">unit of length</a> has a corresponding unit of area, namely the area of a square with the given side length. Thus areas can be measured in <a href="/wiki/Square_metre" title="Square metre">square metres</a> (m<sup>2</sup>), square centimetres (cm<sup>2</sup>), square millimetres (mm<sup>2</sup>), <a href="/wiki/Square_kilometre" title="Square kilometre">square kilometres</a> (km<sup>2</sup>), <a href="/wiki/Square_foot" title="Square foot">square feet</a> (ft<sup>2</sup>), <a href="/wiki/Square_yard" title="Square yard">square yards</a> (yd<sup>2</sup>), <a href="/wiki/Square_mile" title="Square mile">square miles</a> (mi<sup>2</sup>), and so forth.<sup id="cite_ref-BIPM2006Ch5_13-0" class="reference"><a href="#cite_note-BIPM2006Ch5-13"><span class="cite-bracket">&#91;</span>13<span class="cite-bracket">&#93;</span></a></sup> Algebraically, these units can be thought of as the <a href="/wiki/Square_(algebra)" title="Square (algebra)">squares</a> of the corresponding length units. </p><p>The SI unit of area is the square metre, which is considered an <a href="/wiki/SI_derived_unit" title="SI derived unit">SI derived unit</a>.<sup id="cite_ref-B_3-1" class="reference"><a href="#cite_note-B-3"><span class="cite-bracket">&#91;</span>3<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Conversions">Conversions</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=3" title="Edit section: Conversions"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Area_conversion_-_square_mm_in_a_square_cm.png" class="mw-file-description"><img alt="A diagram showing the conversion factor between different areas" src="//upload.wikimedia.org/wikipedia/commons/thumb/8/81/Area_conversion_-_square_mm_in_a_square_cm.png/220px-Area_conversion_-_square_mm_in_a_square_cm.png" decoding="async" width="220" height="185" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/81/Area_conversion_-_square_mm_in_a_square_cm.png/330px-Area_conversion_-_square_mm_in_a_square_cm.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/81/Area_conversion_-_square_mm_in_a_square_cm.png/440px-Area_conversion_-_square_mm_in_a_square_cm.png 2x" data-file-width="831" data-file-height="699" /></a><figcaption>Although there are 10 mm in 1 cm, there are 100 mm<sup>2</sup> in 1 cm<sup>2</sup>.</figcaption></figure> <p>Calculation of the area of a square whose length and width are 1 metre would be: </p><p>1 metre × 1 metre = 1&#160;m<sup>2</sup> </p><p>and so, a rectangle with different sides (say length of 3 metres and width of 2 metres) would have an area in square units that can be calculated as: </p><p>3 metres × 2 metres = 6&#160;m<sup>2</sup>. This is equivalent to 6 million square millimetres. Other useful conversions are: </p> <ul><li>1 square kilometre = <a href="/wiki/Million" class="mw-redirect" title="Million">1,000,000</a> square metres</li> <li>1 square metre = <a href="/wiki/10000_(number)" class="mw-redirect" title="10000 (number)">10,000</a> square centimetres = 1,000,000 square millimetres</li> <li>1 square centimetre = <a href="/wiki/100_(number)" class="mw-redirect" title="100 (number)">100</a> square millimetres.</li></ul> <div class="mw-heading mw-heading4"><h4 id="Non-metric_units">Non-metric units</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=4" title="Edit section: Non-metric units"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In non-metric units, the conversion between two square units is the <a href="/wiki/Square_(algebra)" title="Square (algebra)">square</a> of the conversion between the corresponding length units. </p> <dl><dd>1 <a href="/wiki/Foot_(unit)" title="Foot (unit)">foot</a> = 12 <a href="/wiki/Inch" title="Inch">inches</a>,</dd></dl> <p>the relationship between square feet and square inches is </p> <dl><dd>1 square foot = 144 square inches,</dd></dl> <p>where 144 = 12<sup>2</sup> = 12 × 12. Similarly: </p> <ul><li>1 square yard = <a href="/wiki/9_(number)" class="mw-redirect" title="9 (number)">9</a> square feet</li> <li>1 square mile = 3,097,600 square yards = 27,878,400 square feet</li></ul> <p>In addition, conversion factors include: </p> <ul><li>1 square inch = 6.4516 square centimetres</li> <li>1 square foot = <span style="white-space:nowrap">0.092<span style="margin-left:0.25em">903</span><span style="margin-left:0.25em">04</span></span> square metres</li> <li>1 square yard = <span style="white-space:nowrap">0.836<span style="margin-left:0.25em">127</span><span style="margin-left:0.25em">36</span></span> square metres</li> <li>1 square mile = <span style="white-space:nowrap">2.589<span style="margin-left:0.25em">988</span><span style="margin-left:0.25em">110</span><span style="margin-left:0.25em">336</span></span> square kilometres</li></ul> <div class="mw-heading mw-heading3"><h3 id="Other_units_including_historical">Other units including historical</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=5" title="Edit section: Other units including historical"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Category:Units_of_area" title="Category:Units of area">Category:Units of area</a></div> <p>There are several other common units for area. The <a href="/wiki/Are_(unit)" class="mw-redirect" title="Are (unit)">are</a> was the original unit of area in the <a href="/wiki/Metric_system" title="Metric system">metric system</a>, with: </p> <ul><li>1 are = 100 square metres</li></ul> <p>Though the are has fallen out of use, the <a href="/wiki/Hectare" title="Hectare">hectare</a> is still commonly used to measure land:<sup id="cite_ref-BIPM2006Ch5_13-1" class="reference"><a href="#cite_note-BIPM2006Ch5-13"><span class="cite-bracket">&#91;</span>13<span class="cite-bracket">&#93;</span></a></sup> </p> <ul><li>1 hectare = 100 ares = 10,000 square metres = 0.01 square kilometres</li></ul> <p>Other uncommon metric units of area include the <a href="/wiki/Tetrad_(unit_of_area)" class="mw-redirect" title="Tetrad (unit of area)">tetrad</a>, the <a href="/wiki/Hectad" title="Hectad">hectad</a>, and the <a href="/wiki/Myriad_(area)" title="Myriad (area)">myriad</a>. </p><p>The <a href="/wiki/Acre" title="Acre">acre</a> is also commonly used to measure land areas, where </p> <ul><li>1 acre = 4,840 square yards = 43,560 square feet.</li></ul> <p>An acre is approximately 40% of a hectare. </p><p>On the atomic scale, area is measured in units of <a href="/wiki/Barn_(unit)" title="Barn (unit)">barns</a>, such that:<sup id="cite_ref-BIPM2006Ch5_13-2" class="reference"><a href="#cite_note-BIPM2006Ch5-13"><span class="cite-bracket">&#91;</span>13<span class="cite-bracket">&#93;</span></a></sup> </p> <ul><li>1 barn = 10<sup>−28</sup> square meters.</li></ul> <p>The barn is commonly used in describing the cross-sectional area of interaction in <a href="/wiki/Nuclear_physics" title="Nuclear physics">nuclear physics</a>.<sup id="cite_ref-BIPM2006Ch5_13-3" class="reference"><a href="#cite_note-BIPM2006Ch5-13"><span class="cite-bracket">&#91;</span>13<span class="cite-bracket">&#93;</span></a></sup> </p><p>In <a href="/wiki/South_Asia" title="South Asia">South Asia</a> (mainly Indians), although the countries use SI units as official, many South Asians still use traditional units. Each administrative division has its own area unit, some of them have same names, but with different values. There's no official consensus about the traditional units values. Thus, the conversions between the SI units and the traditional units may have different results, depending on what reference that has been used.<sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">&#91;</span>14<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-15" class="reference"><a href="#cite_note-15"><span class="cite-bracket">&#91;</span>15<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-16" class="reference"><a href="#cite_note-16"><span class="cite-bracket">&#91;</span>16<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-17" class="reference"><a href="#cite_note-17"><span class="cite-bracket">&#91;</span>17<span class="cite-bracket">&#93;</span></a></sup> </p><p>Some traditional South Asian units that have fixed value: </p> <ul><li>1 Killa = 1 acre</li> <li>1 Ghumaon = 1 acre</li> <li>1 Kanal = 0.125 acre (1 acre = 8 kanal)</li> <li>1 Decimal = 48.4 square yards</li> <li>1 Chatak = 180 square feet</li></ul> <div class="mw-heading mw-heading2"><h2 id="History">History</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=6" title="Edit section: History"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Circle_area">Circle area</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=7" title="Edit section: Circle area"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Area_of_a_circle#History" title="Area of a circle">Area of a circle §&#160;History</a></div> <p>In the 5th century BCE, <a href="/wiki/Hippocrates_of_Chios" title="Hippocrates of Chios">Hippocrates of Chios</a> was the first to show that the area of a disk (the region enclosed by a circle) is proportional to the square of its diameter, as part of his <a href="/wiki/Quadrature_(mathematics)" class="mw-redirect" title="Quadrature (mathematics)">quadrature</a> of the <a href="/wiki/Lune_of_Hippocrates" title="Lune of Hippocrates">lune of Hippocrates</a>,<sup id="cite_ref-heath_18-0" class="reference"><a href="#cite_note-heath-18"><span class="cite-bracket">&#91;</span>18<span class="cite-bracket">&#93;</span></a></sup> but did not identify the <a href="/wiki/Constant_of_proportionality" class="mw-redirect" title="Constant of proportionality">constant of proportionality</a>. <a href="/wiki/Eudoxus_of_Cnidus" title="Eudoxus of Cnidus">Eudoxus of Cnidus</a>, also in the 5th century BCE, also found that the area of a disk is proportional to its radius squared.<sup id="cite_ref-19" class="reference"><a href="#cite_note-19"><span class="cite-bracket">&#91;</span>19<span class="cite-bracket">&#93;</span></a></sup> </p><p>Subsequently, Book I of <a href="/wiki/Euclid%27s_Elements" title="Euclid&#39;s Elements">Euclid's <i>Elements</i></a> dealt with equality of areas between two-dimensional figures. The mathematician <a href="/wiki/Archimedes" title="Archimedes">Archimedes</a> used the tools of <a href="/wiki/Euclidean_geometry" title="Euclidean geometry">Euclidean geometry</a> to show that the area inside a circle is equal to that of a <a href="/wiki/Right_triangle" title="Right triangle">right triangle</a> whose base has the length of the circle's circumference and whose height equals the circle's radius, in his book <i><a href="/wiki/Measurement_of_a_Circle" title="Measurement of a Circle">Measurement of a Circle</a></i>. (The circumference is 2<span class="texhtml mvar" style="font-style:italic;">π</span><i>r</i>, and the area of a triangle is half the base times the height, yielding the area <span class="texhtml mvar" style="font-style:italic;">π</span><i>r</i><sup>2</sup> for the disk.) Archimedes approximated the value of <span class="texhtml mvar" style="font-style:italic;">π</span> (and hence the area of a unit-radius circle) with <a href="/wiki/Area_of_a_disk#Archimedes&#39;_doubling_method" class="mw-redirect" title="Area of a disk">his doubling method</a>, in which he inscribed a regular triangle in a circle and noted its area, then doubled the number of sides to give a regular <a href="/wiki/Hexagon" title="Hexagon">hexagon</a>, then repeatedly doubled the number of sides as the polygon's area got closer and closer to that of the circle (and did the same with <a href="/wiki/Circumscribed_polygon" class="mw-redirect" title="Circumscribed polygon">circumscribed polygons</a>). </p> <div class="mw-heading mw-heading3"><h3 id="Triangle_area">Triangle area</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=8" title="Edit section: Triangle area"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="excerpt-block"><style data-mw-deduplicate="TemplateStyles:r1066933788">.mw-parser-output .excerpt-hat .mw-editsection-like{font-style:normal}</style><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable dablink excerpt-hat selfref">This section is an excerpt from <a href="/wiki/Area_of_a_triangle#History" title="Area of a triangle">Area of a triangle § History</a>.<span class="mw-editsection-like plainlinks"><span class="mw-editsection-bracket">[</span><a class="external text" href="https://en.wikipedia.org/w/index.php?title=Area_of_a_triangle&amp;action=edit#History">edit</a><span class="mw-editsection-bracket">]</span></span></div><div class="excerpt"> <p><a href="/wiki/Heron_of_Alexandria" class="mw-redirect" title="Heron of Alexandria">Heron of Alexandria</a> found what is known as <a href="/wiki/Heron%27s_formula" title="Heron&#39;s formula">Heron's formula</a> for the area of a triangle in terms of its sides, and a proof can be found in his book, <i>Metrica</i>, written around 60 CE. It has been suggested that <a href="/wiki/Archimedes" title="Archimedes">Archimedes</a> knew the formula over two centuries earlier,<sup id="cite_ref-20" class="reference"><a href="#cite_note-20"><span class="cite-bracket">&#91;</span>20<span class="cite-bracket">&#93;</span></a></sup> and since <i>Metrica</i> is a collection of the mathematical knowledge available in the ancient world, it is possible that the formula predates the reference given in that work.<sup id="cite_ref-21" class="reference"><a href="#cite_note-21"><span class="cite-bracket">&#91;</span>21<span class="cite-bracket">&#93;</span></a></sup> In 300 BCE Greek mathematician <a href="/wiki/Euclid" title="Euclid">Euclid</a> proved that the area of a triangle is half that of a parallelogram with the same base and height in his book <i>Elements of Geometry</i>.<sup id="cite_ref-22" class="reference"><a href="#cite_note-22"><span class="cite-bracket">&#91;</span>22<span class="cite-bracket">&#93;</span></a></sup> </p><p>In 499 <a href="/wiki/Aryabhata" title="Aryabhata">Aryabhata</a>, a great <a href="/wiki/Mathematician" title="Mathematician">mathematician</a>-<a href="/wiki/Astronomer" title="Astronomer">astronomer</a> from the classical age of <a href="/wiki/Indian_mathematics" title="Indian mathematics">Indian mathematics</a> and <a href="/wiki/Indian_astronomy" title="Indian astronomy">Indian astronomy</a>, expressed the area of a triangle as one-half the base times the height in the <i><a href="/wiki/Aryabhatiya" title="Aryabhatiya">Aryabhatiya</a></i>.<sup id="cite_ref-23" class="reference"><a href="#cite_note-23"><span class="cite-bracket">&#91;</span>23<span class="cite-bracket">&#93;</span></a></sup> </p> A formula equivalent to Heron's was discovered by the Chinese independently of the Greeks. It was published in 1247 in <i>Shushu Jiuzhang</i> ("<a href="/wiki/Mathematical_Treatise_in_Nine_Sections" title="Mathematical Treatise in Nine Sections">Mathematical Treatise in Nine Sections</a>"), written by <a href="/wiki/Qin_Jiushao" title="Qin Jiushao">Qin Jiushao</a>.<sup id="cite_ref-24" class="reference"><a href="#cite_note-24"><span class="cite-bracket">&#91;</span>24<span class="cite-bracket">&#93;</span></a></sup></div></div> <div class="mw-heading mw-heading3"><h3 id="Quadrilateral_area">Quadrilateral area</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=9" title="Edit section: Quadrilateral area"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In the 7th century CE, <a href="/wiki/Brahmagupta" title="Brahmagupta">Brahmagupta</a> developed a formula, now known as <a href="/wiki/Brahmagupta%27s_formula" title="Brahmagupta&#39;s formula">Brahmagupta's formula</a>, for the area of a <a href="/wiki/Cyclic_quadrilateral" title="Cyclic quadrilateral">cyclic quadrilateral</a> (a <a href="/wiki/Quadrilateral" title="Quadrilateral">quadrilateral</a> <a href="/wiki/Inscribed_figure" title="Inscribed figure">inscribed</a> in a circle) in terms of its sides. In 1842, the German mathematicians <a href="/wiki/Carl_Anton_Bretschneider" title="Carl Anton Bretschneider">Carl Anton Bretschneider</a> and <a href="/wiki/Karl_Georg_Christian_von_Staudt" title="Karl Georg Christian von Staudt">Karl Georg Christian von Staudt</a> independently found a formula, known as <a href="/wiki/Bretschneider%27s_formula" title="Bretschneider&#39;s formula">Bretschneider's formula</a>, for the area of any quadrilateral. </p> <div class="mw-heading mw-heading3"><h3 id="General_polygon_area">General polygon area</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=10" title="Edit section: General polygon area"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The development of <a href="/wiki/Cartesian_coordinate_system" title="Cartesian coordinate system">Cartesian coordinates</a> by <a href="/wiki/Ren%C3%A9_Descartes" title="René Descartes">René Descartes</a> in the 17th century allowed the development of the <a href="/wiki/Shoelace_formula" title="Shoelace formula">surveyor's formula</a> for the area of any polygon with known <a href="/wiki/Vertex_(geometry)" title="Vertex (geometry)">vertex</a> locations by <a href="/wiki/Gauss" class="mw-redirect" title="Gauss">Gauss</a> in the 19th century. </p> <div class="mw-heading mw-heading3"><h3 id="Areas_determined_using_calculus">Areas determined using calculus</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=11" title="Edit section: Areas determined using calculus"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The development of <a href="/wiki/Integral_calculus" class="mw-redirect" title="Integral calculus">integral calculus</a> in the late 17th century provided tools that could subsequently be used for computing more complicated areas, such as the area of an <a href="/wiki/Ellipse#Area" title="Ellipse">ellipse</a> and the <a href="/wiki/Surface_area" title="Surface area">surface areas</a> of various curved three-dimensional objects. </p> <div class="mw-heading mw-heading2"><h2 id="Area_formulas">Area formulas</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=12" title="Edit section: Area formulas"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Polygon_formulas">Polygon formulas</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=13" title="Edit section: Polygon formulas"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Polygon#Area" title="Polygon">Polygon §&#160;Area</a></div> <p>For a non-self-intersecting (<a href="/wiki/Simple_polygon" title="Simple polygon">simple</a>) polygon, the <a href="/wiki/Cartesian_coordinate_system" title="Cartesian coordinate system">Cartesian coordinates</a> <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle (x_{i},y_{i})}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mo stretchy="false">(</mo> <msub> <mi>x</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>i</mi> </mrow> </msub> <mo>,</mo> <msub> <mi>y</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>i</mi> </mrow> </msub> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle (x_{i},y_{i})}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/d6dbb919b91ccacf17ed47898048428a1baf9703" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:6.912ex; height:2.843ex;" alt="{\displaystyle (x_{i},y_{i})}"></span> (<i>i</i>=0, 1, ..., <i>n</i>-1) of whose <i>n</i> <a href="/wiki/Vertex_(geometry)" title="Vertex (geometry)">vertices</a> are known, the area is given by the <a href="/wiki/Shoelace_formula" title="Shoelace formula">surveyor's formula</a>:<sup id="cite_ref-25" class="reference"><a href="#cite_note-25"><span class="cite-bracket">&#91;</span>25<span class="cite-bracket">&#93;</span></a></sup> </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A={\frac {1}{2}}{\Biggl \vert }\sum _{i=0}^{n-1}(x_{i}y_{i+1}-x_{i+1}y_{i}){\Biggr \vert }}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mn>1</mn> <mn>2</mn> </mfrac> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mrow class="MJX-TeXAtom-OPEN"> <mo maxsize="2.470em" minsize="2.470em">|</mo> </mrow> </mrow> <munderover> <mo>&#x2211;<!-- ∑ --></mo> <mrow class="MJX-TeXAtom-ORD"> <mi>i</mi> <mo>=</mo> <mn>0</mn> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mi>n</mi> <mo>&#x2212;<!-- − --></mo> <mn>1</mn> </mrow> </munderover> <mo stretchy="false">(</mo> <msub> <mi>x</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>i</mi> </mrow> </msub> <msub> <mi>y</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>i</mi> <mo>+</mo> <mn>1</mn> </mrow> </msub> <mo>&#x2212;<!-- − --></mo> <msub> <mi>x</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>i</mi> <mo>+</mo> <mn>1</mn> </mrow> </msub> <msub> <mi>y</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>i</mi> </mrow> </msub> <mo stretchy="false">)</mo> <mrow class="MJX-TeXAtom-ORD"> <mrow class="MJX-TeXAtom-CLOSE"> <mo maxsize="2.470em" minsize="2.470em">|</mo> </mrow> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A={\frac {1}{2}}{\Biggl \vert }\sum _{i=0}^{n-1}(x_{i}y_{i+1}-x_{i+1}y_{i}){\Biggr \vert }}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/75a7a8f3daee3a89bf30d86734f007b563007a4f" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -3.005ex; width:28.863ex; height:7.343ex;" alt="{\displaystyle A={\frac {1}{2}}{\Biggl \vert }\sum _{i=0}^{n-1}(x_{i}y_{i+1}-x_{i+1}y_{i}){\Biggr \vert }}"></span></dd></dl> <p>where when <i>i</i>=<i>n</i>-1, then <i>i</i>+1 is expressed as <a href="/wiki/Modular_arithmetic" title="Modular arithmetic">modulus</a> <i>n</i> and so refers to 0. </p> <div class="mw-heading mw-heading4"><h4 id="Rectangles">Rectangles</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=14" title="Edit section: Rectangles"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:RectangleLengthWidth.svg" class="mw-file-description"><img alt="A rectangle with length and width labelled" src="//upload.wikimedia.org/wikipedia/commons/thumb/8/8d/RectangleLengthWidth.svg/170px-RectangleLengthWidth.svg.png" decoding="async" width="170" height="131" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/8d/RectangleLengthWidth.svg/255px-RectangleLengthWidth.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/8d/RectangleLengthWidth.svg/340px-RectangleLengthWidth.svg.png 2x" data-file-width="220" data-file-height="170" /></a><figcaption>The area of this rectangle is&#160;<span class="texhtml mvar" style="font-style:italic;">lw</span>.</figcaption></figure> <p>The most basic area formula is the formula for the area of a <a href="/wiki/Rectangle" title="Rectangle">rectangle</a>. Given a rectangle with length <span class="texhtml mvar" style="font-style:italic;">l</span> and width <span class="texhtml mvar" style="font-style:italic;">w</span>, the formula for the area is:<sup id="cite_ref-AF_2-1" class="reference"><a href="#cite_note-AF-2"><span class="cite-bracket">&#91;</span>2<span class="cite-bracket">&#93;</span></a></sup> </p> <dl><dd><span class="texhtml texhtml-big" style="font-size:165%;"><i>A</i> = <i>lw</i></span> &#160;(rectangle).</dd></dl> <p>That is, the area of the rectangle is the length multiplied by the width. As a special case, as <span class="texhtml"><i>l</i> = <i>w</i></span> in the case of a square, the area of a square with side length <span class="texhtml mvar" style="font-style:italic;">s</span> is given by the formula:<sup id="cite_ref-MathWorld_1-3" class="reference"><a href="#cite_note-MathWorld-1"><span class="cite-bracket">&#91;</span>1<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-AF_2-2" class="reference"><a href="#cite_note-AF-2"><span class="cite-bracket">&#91;</span>2<span class="cite-bracket">&#93;</span></a></sup> </p> <dl><dd><span class="texhtml texhtml-big" style="font-size:165%;"><i>A</i> = <i>s</i><sup>2</sup></span> &#160;(square).</dd></dl> <p>The formula for the area of a rectangle follows directly from the basic properties of area, and is sometimes taken as a <a href="/wiki/Definition" title="Definition">definition</a> or <a href="/wiki/Axiom" title="Axiom">axiom</a>. On the other hand, if <a href="/wiki/Geometry" title="Geometry">geometry</a> is developed before <a href="/wiki/Arithmetic" title="Arithmetic">arithmetic</a>, this formula can be used to define <a href="/wiki/Multiplication" title="Multiplication">multiplication</a> of <a href="/wiki/Real_number" title="Real number">real numbers</a>. </p> <div class="mw-heading mw-heading4"><h4 id="Dissection,_parallelograms,_and_triangles"><span id="Dissection.2C_parallelograms.2C_and_triangles"></span>Dissection, parallelograms, and triangles</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=15" title="Edit section: Dissection, parallelograms, and triangles"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main articles: <a href="/wiki/Triangle_area" class="mw-redirect" title="Triangle area">Triangle area</a> and <a href="/wiki/Parallelogram#Area_formula" title="Parallelogram">Parallelogram §&#160;Area formula</a></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:ParallelogramArea.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/ParallelogramArea.svg/170px-ParallelogramArea.svg.png" decoding="async" width="170" height="223" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/1c/ParallelogramArea.svg/255px-ParallelogramArea.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/1c/ParallelogramArea.svg/340px-ParallelogramArea.svg.png 2x" data-file-width="204" data-file-height="268" /></a><figcaption>A parallelogram can be cut up and re-arranged to form a rectangle.</figcaption></figure> <p>Most other simple formulas for area follow from the method of <a href="/wiki/Dissection_(geometry)" class="mw-redirect" title="Dissection (geometry)">dissection</a>. This involves cutting a shape into pieces, whose areas must <a href="/wiki/Addition" title="Addition">sum</a> to the area of the original shape. For an example, any <a href="/wiki/Parallelogram" title="Parallelogram">parallelogram</a> can be subdivided into a <a href="/wiki/Trapezoid" title="Trapezoid">trapezoid</a> and a <a href="/wiki/Right_triangle" title="Right triangle">right triangle</a>, as shown in figure to the left. If the triangle is moved to the other side of the trapezoid, then the resulting figure is a rectangle. It follows that the area of the parallelogram is the same as the area of the rectangle:<sup id="cite_ref-AF_2-3" class="reference"><a href="#cite_note-AF-2"><span class="cite-bracket">&#91;</span>2<span class="cite-bracket">&#93;</span></a></sup> </p> <dl><dd><span class="texhtml texhtml-big" style="font-size:165%;"><i>A</i> = <i>bh</i></span> &#160;(parallelogram).</dd></dl> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:TriangleArea.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/7/7c/TriangleArea.svg/170px-TriangleArea.svg.png" decoding="async" width="170" height="124" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/7c/TriangleArea.svg/255px-TriangleArea.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/7c/TriangleArea.svg/340px-TriangleArea.svg.png 2x" data-file-width="220" data-file-height="160" /></a><figcaption>A parallelogram split into two equal triangles</figcaption></figure> <p>However, the same parallelogram can also be cut along a <a href="/wiki/Diagonal" title="Diagonal">diagonal</a> into two <a href="/wiki/Congruence_(geometry)" title="Congruence (geometry)">congruent</a> triangles, as shown in the figure to the right. It follows that the area of each <a href="/wiki/Triangle" title="Triangle">triangle</a> is half the area of the parallelogram:<sup id="cite_ref-AF_2-4" class="reference"><a href="#cite_note-AF-2"><span class="cite-bracket">&#91;</span>2<span class="cite-bracket">&#93;</span></a></sup> </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A={\frac {1}{2}}bh}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mn>1</mn> <mn>2</mn> </mfrac> </mrow> <mi>b</mi> <mi>h</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A={\frac {1}{2}}bh}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/78bb1af1b9493a6b26955f711ae9b95a68f671be" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.838ex; width:9.177ex; height:5.176ex;" alt="{\displaystyle A={\frac {1}{2}}bh}"></span> &#160;(triangle).</dd></dl> <p>Similar arguments can be used to find area formulas for the <a href="/wiki/Trapezoid" title="Trapezoid">trapezoid</a><sup id="cite_ref-26" class="reference"><a href="#cite_note-26"><span class="cite-bracket">&#91;</span>26<span class="cite-bracket">&#93;</span></a></sup> as well as more complicated <a href="/wiki/Polygon" title="Polygon">polygons</a>.<sup id="cite_ref-27" class="reference"><a href="#cite_note-27"><span class="cite-bracket">&#91;</span>27<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Area_of_curved_shapes">Area of curved shapes</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=16" title="Edit section: Area of curved shapes"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading4"><h4 id="Circles">Circles</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=17" title="Edit section: Circles"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:CircleArea.svg" class="mw-file-description"><img alt="A circle divided into many sectors can be re-arranged roughly to form a parallelogram" src="//upload.wikimedia.org/wikipedia/commons/thumb/f/fb/CircleArea.svg/220px-CircleArea.svg.png" decoding="async" width="220" height="238" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/fb/CircleArea.svg/330px-CircleArea.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/fb/CircleArea.svg/440px-CircleArea.svg.png 2x" data-file-width="240" data-file-height="260" /></a><figcaption>A circle can be divided into <a href="/wiki/Circular_sector" title="Circular sector">sectors</a> which rearrange to form an approximate <a href="/wiki/Parallelogram" title="Parallelogram">parallelogram</a>.</figcaption></figure> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Area_of_a_circle" title="Area of a circle">Area of a circle</a></div> <p>The formula for the area of a <a href="/wiki/Circle" title="Circle">circle</a> (more properly called the area enclosed by a circle or the area of a <a href="/wiki/Disk_(mathematics)" title="Disk (mathematics)">disk</a>) is based on a similar method. Given a circle of radius <span class="texhtml"><i>r</i></span>, it is possible to partition the circle into <a href="/wiki/Circular_sector" title="Circular sector">sectors</a>, as shown in the figure to the right. Each sector is approximately triangular in shape, and the sectors can be rearranged to form an approximate parallelogram. The height of this parallelogram is <span class="texhtml"><i>r</i></span>, and the width is half the <a href="/wiki/Circumference" title="Circumference">circumference</a> of the circle, or <span class="texhtml">π<i>r</i></span>. Thus, the total area of the circle is <span class="texhtml">π<i>r</i><sup>2</sup></span>:<sup id="cite_ref-AF_2-5" class="reference"><a href="#cite_note-AF-2"><span class="cite-bracket">&#91;</span>2<span class="cite-bracket">&#93;</span></a></sup> </p> <dl><dd><span class="texhtml texhtml-big" style="font-size:165%;"><i>A</i> = π<i>r</i><sup>2</sup></span> &#160;(circle).</dd></dl> <p>Though the dissection used in this formula is only approximate, the error becomes smaller and smaller as the circle is partitioned into more and more sectors. The <a href="/wiki/Limit_(mathematics)" title="Limit (mathematics)">limit</a> of the areas of the approximate parallelograms is exactly <span class="texhtml">π<i>r</i><sup>2</sup></span>, which is the area of the circle.<sup id="cite_ref-Surveyor_28-0" class="reference"><a href="#cite_note-Surveyor-28"><span class="cite-bracket">&#91;</span>28<span class="cite-bracket">&#93;</span></a></sup> </p><p>This argument is actually a simple application of the ideas of <a href="/wiki/Calculus" title="Calculus">calculus</a>. In ancient times, the <a href="/wiki/Method_of_exhaustion" title="Method of exhaustion">method of exhaustion</a> was used in a similar way to find the area of the circle, and this method is now recognized as a precursor to <a href="/wiki/Integral_calculus" class="mw-redirect" title="Integral calculus">integral calculus</a>. Using modern methods, the area of a circle can be computed using a <a href="/wiki/Definite_integral" class="mw-redirect" title="Definite integral">definite integral</a>: </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A\;=\;2\int _{-r}^{r}{\sqrt {r^{2}-x^{2}}}\,dx\;=\;\pi r^{2}.}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mspace width="thickmathspace" /> <mo>=</mo> <mspace width="thickmathspace" /> <mn>2</mn> <msubsup> <mo>&#x222B;<!-- ∫ --></mo> <mrow class="MJX-TeXAtom-ORD"> <mo>&#x2212;<!-- − --></mo> <mi>r</mi> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mi>r</mi> </mrow> </msubsup> <mrow class="MJX-TeXAtom-ORD"> <msqrt> <msup> <mi>r</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mo>&#x2212;<!-- − --></mo> <msup> <mi>x</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> </msqrt> </mrow> <mspace width="thinmathspace" /> <mi>d</mi> <mi>x</mi> <mspace width="thickmathspace" /> <mo>=</mo> <mspace width="thickmathspace" /> <mi>&#x03C0;<!-- π --></mi> <msup> <mi>r</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mo>.</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A\;=\;2\int _{-r}^{r}{\sqrt {r^{2}-x^{2}}}\,dx\;=\;\pi r^{2}.}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/e6b8d5ed507b330b0f07bf4310d64c8b687ea2ac" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.505ex; width:32.668ex; height:6.009ex;" alt="{\displaystyle A\;=\;2\int _{-r}^{r}{\sqrt {r^{2}-x^{2}}}\,dx\;=\;\pi r^{2}.}"></span></dd></dl> <div class="mw-heading mw-heading4"><h4 id="Ellipses">Ellipses</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=18" title="Edit section: Ellipses"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Ellipse#Area" title="Ellipse">Ellipse §&#160;Area</a></div> <p>The formula for the area enclosed by an <a href="/wiki/Ellipse" title="Ellipse">ellipse</a> is related to the formula of a circle; for an ellipse with <a href="/wiki/Semi-major_axis" class="mw-redirect" title="Semi-major axis">semi-major</a> and <a href="/wiki/Semi-minor_axis" class="mw-redirect" title="Semi-minor axis">semi-minor</a> axes <span class="texhtml"><i>x</i></span> and <span class="texhtml"><i>y</i></span> the formula is:<sup id="cite_ref-AF_2-6" class="reference"><a href="#cite_note-AF-2"><span class="cite-bracket">&#91;</span>2<span class="cite-bracket">&#93;</span></a></sup> </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A=\pi xy.}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mi>&#x03C0;<!-- π --></mi> <mi>x</mi> <mi>y</mi> <mo>.</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A=\pi xy.}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/a81da558d3d525f9ff7688980d2788087713390f" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:9.306ex; height:2.509ex;" alt="{\displaystyle A=\pi xy.}"></span></dd></dl> <div class="mw-heading mw-heading3"><h3 id="Non-planar_surface_area">Non-planar surface area</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=19" title="Edit section: Non-planar surface area"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Surface_area" title="Surface area">Surface area</a></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Archimedes_sphere_and_cylinder.svg" class="mw-file-description"><img alt="A blue sphere inside a cylinder of the same height and radius" src="//upload.wikimedia.org/wikipedia/commons/thumb/7/70/Archimedes_sphere_and_cylinder.svg/220px-Archimedes_sphere_and_cylinder.svg.png" decoding="async" width="220" height="238" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/70/Archimedes_sphere_and_cylinder.svg/330px-Archimedes_sphere_and_cylinder.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/70/Archimedes_sphere_and_cylinder.svg/440px-Archimedes_sphere_and_cylinder.svg.png 2x" data-file-width="426" data-file-height="461" /></a><figcaption><a href="/wiki/Archimedes" title="Archimedes">Archimedes</a> showed that the surface area of a <a href="/wiki/Sphere" title="Sphere">sphere</a> is exactly four times the area of a flat <a href="/wiki/Disk_(mathematics)" title="Disk (mathematics)">disk</a> of the same radius, and the volume enclosed by the sphere is exactly 2/3 of the volume of a <a href="/wiki/Cylinder_(geometry)" class="mw-redirect" title="Cylinder (geometry)">cylinder</a> of the same height and radius.</figcaption></figure> <p>Most basic formulas for <a href="/wiki/Surface_area" title="Surface area">surface area</a> can be obtained by cutting surfaces and flattening them out (see: <a href="/wiki/Developable_surface" title="Developable surface">developable surfaces</a>). For example, if the side surface of a <a href="/wiki/Cylinder_(geometry)" class="mw-redirect" title="Cylinder (geometry)">cylinder</a> (or any <a href="/wiki/Prism_(geometry)" title="Prism (geometry)">prism</a>) is cut lengthwise, the surface can be flattened out into a rectangle. Similarly, if a cut is made along the side of a <a href="/wiki/Cone_(geometry)" class="mw-redirect" title="Cone (geometry)">cone</a>, the side surface can be flattened out into a sector of a circle, and the resulting area computed. </p><p>The formula for the surface area of a <a href="/wiki/Sphere" title="Sphere">sphere</a> is more difficult to derive: because a sphere has nonzero <a href="/wiki/Gaussian_curvature" title="Gaussian curvature">Gaussian curvature</a>, it cannot be flattened out. The formula for the surface area of a sphere was first obtained by <a href="/wiki/Archimedes" title="Archimedes">Archimedes</a> in his work <i><a href="/wiki/On_the_Sphere_and_Cylinder" title="On the Sphere and Cylinder">On the Sphere and Cylinder</a></i>. The formula is:<sup id="cite_ref-MathWorldSurfaceArea_6-1" class="reference"><a href="#cite_note-MathWorldSurfaceArea-6"><span class="cite-bracket">&#91;</span>6<span class="cite-bracket">&#93;</span></a></sup> </p> <dl><dd><span class="texhtml"><i>A</i> = 4<i>πr</i><sup>2</sup></span> &#160;(sphere),</dd></dl> <p>where <span class="texhtml"><i>r</i></span> is the radius of the sphere. As with the formula for the area of a circle, any derivation of this formula inherently uses methods similar to <a href="/wiki/Calculus" title="Calculus">calculus</a>. </p> <div class="mw-heading mw-heading3"><h3 id="General_formulas">General formulas</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=20" title="Edit section: General formulas"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading4"><h4 id="Areas_of_2-dimensional_figures">Areas of 2-dimensional figures</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=21" title="Edit section: Areas of 2-dimensional figures"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Triangle_GeometryArea.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/e/ec/Triangle_GeometryArea.svg/220px-Triangle_GeometryArea.svg.png" decoding="async" width="220" height="55" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/ec/Triangle_GeometryArea.svg/330px-Triangle_GeometryArea.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/ec/Triangle_GeometryArea.svg/440px-Triangle_GeometryArea.svg.png 2x" data-file-width="473" data-file-height="119" /></a><figcaption>Triangle area <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A={\tfrac {b\cdot h}{2}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="false" scriptlevel="0"> <mfrac> <mrow> <mi>b</mi> <mo>&#x22C5;<!-- ⋅ --></mo> <mi>h</mi> </mrow> <mn>2</mn> </mfrac> </mstyle> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A={\tfrac {b\cdot h}{2}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/3d4d00ca1155c1418f0f6dcef9bdc0c9e4bb6236" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.171ex; width:7.787ex; height:3.676ex;" alt="{\displaystyle A={\tfrac {b\cdot h}{2}}}"></span></figcaption></figure> <ul><li>A <a href="/wiki/Triangle" title="Triangle">triangle</a>: <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\tfrac {1}{2}}Bh}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="false" scriptlevel="0"> <mfrac> <mn>1</mn> <mn>2</mn> </mfrac> </mstyle> </mrow> <mi>B</mi> <mi>h</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle {\tfrac {1}{2}}Bh}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/f09dd787bfe06fe8b0eb87d06b87f8d2c05b91ea" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.171ex; width:4.761ex; height:3.509ex;" alt="{\displaystyle {\tfrac {1}{2}}Bh}"></span> (where <i>B</i> is any side, and <i>h</i> is the distance from the line on which <i>B</i> lies to the other vertex of the triangle). This formula can be used if the height <i>h</i> is known. If the lengths of the three sides are known then <i><a href="/wiki/Heron%27s_formula" title="Heron&#39;s formula">Heron's formula</a></i> can be used: <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\sqrt {s(s-a)(s-b)(s-c)}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mrow class="MJX-TeXAtom-ORD"> <msqrt> <mi>s</mi> <mo stretchy="false">(</mo> <mi>s</mi> <mo>&#x2212;<!-- − --></mo> <mi>a</mi> <mo stretchy="false">)</mo> <mo stretchy="false">(</mo> <mi>s</mi> <mo>&#x2212;<!-- − --></mo> <mi>b</mi> <mo stretchy="false">)</mo> <mo stretchy="false">(</mo> <mi>s</mi> <mo>&#x2212;<!-- − --></mo> <mi>c</mi> <mo stretchy="false">)</mo> </msqrt> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle {\sqrt {s(s-a)(s-b)(s-c)}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/fd7e3feb227eeda3c19b052c797ee19a01a6c467" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.838ex; width:23.869ex; height:4.843ex;" alt="{\displaystyle {\sqrt {s(s-a)(s-b)(s-c)}}}"></span> where <i>a</i>, <i>b</i>, <i>c</i> are the sides of the triangle, and <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle s={\tfrac {1}{2}}(a+b+c)}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>s</mi> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="false" scriptlevel="0"> <mfrac> <mn>1</mn> <mn>2</mn> </mfrac> </mstyle> </mrow> <mo stretchy="false">(</mo> <mi>a</mi> <mo>+</mo> <mi>b</mi> <mo>+</mo> <mi>c</mi> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle s={\tfrac {1}{2}}(a+b+c)}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/ed2c4193212526a50585182f301e85e2f1cdfde8" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.171ex; width:16.571ex; height:3.509ex;" alt="{\displaystyle s={\tfrac {1}{2}}(a+b+c)}"></span> is half of its perimeter.<sup id="cite_ref-AF_2-7" class="reference"><a href="#cite_note-AF-2"><span class="cite-bracket">&#91;</span>2<span class="cite-bracket">&#93;</span></a></sup> If an angle and its two included sides are given, the area is <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\tfrac {1}{2}}ab\sin(C)}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="false" scriptlevel="0"> <mfrac> <mn>1</mn> <mn>2</mn> </mfrac> </mstyle> </mrow> <mi>a</mi> <mi>b</mi> <mi>sin</mi> <mo>&#x2061;<!-- ⁡ --></mo> <mo stretchy="false">(</mo> <mi>C</mi> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle {\tfrac {1}{2}}ab\sin(C)}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/f3719986bc49ddbdd159b5920e995f1c79f0b6c6" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.171ex; width:10.704ex; height:3.509ex;" alt="{\displaystyle {\tfrac {1}{2}}ab\sin(C)}"></span> where <span class="texhtml"><i>C</i></span> is the given angle and <span class="texhtml"><i>a</i></span> and <span class="texhtml"><i>b</i></span> are its included sides.<sup id="cite_ref-AF_2-8" class="reference"><a href="#cite_note-AF-2"><span class="cite-bracket">&#91;</span>2<span class="cite-bracket">&#93;</span></a></sup> If the triangle is graphed on a coordinate plane, a matrix can be used and is simplified to the absolute value of <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\tfrac {1}{2}}(x_{1}y_{2}+x_{2}y_{3}+x_{3}y_{1}-x_{2}y_{1}-x_{3}y_{2}-x_{1}y_{3})}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="false" scriptlevel="0"> <mfrac> <mn>1</mn> <mn>2</mn> </mfrac> </mstyle> </mrow> <mo stretchy="false">(</mo> <msub> <mi>x</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>1</mn> </mrow> </msub> <msub> <mi>y</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mo>+</mo> <msub> <mi>x</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <msub> <mi>y</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>3</mn> </mrow> </msub> <mo>+</mo> <msub> <mi>x</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>3</mn> </mrow> </msub> <msub> <mi>y</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>1</mn> </mrow> </msub> <mo>&#x2212;<!-- − --></mo> <msub> <mi>x</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <msub> <mi>y</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>1</mn> </mrow> </msub> <mo>&#x2212;<!-- − --></mo> <msub> <mi>x</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>3</mn> </mrow> </msub> <msub> <mi>y</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mo>&#x2212;<!-- − --></mo> <msub> <mi>x</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>1</mn> </mrow> </msub> <msub> <mi>y</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>3</mn> </mrow> </msub> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle {\tfrac {1}{2}}(x_{1}y_{2}+x_{2}y_{3}+x_{3}y_{1}-x_{2}y_{1}-x_{3}y_{2}-x_{1}y_{3})}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/5bc87b3de461b79f0fc4f5fde09a0cb00ced460e" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.171ex; width:45.134ex; height:3.509ex;" alt="{\displaystyle {\tfrac {1}{2}}(x_{1}y_{2}+x_{2}y_{3}+x_{3}y_{1}-x_{2}y_{1}-x_{3}y_{2}-x_{1}y_{3})}"></span>. This formula is also known as the <a href="/wiki/Shoelace_formula" title="Shoelace formula">shoelace formula</a> and is an easy way to solve for the area of a coordinate triangle by substituting the 3 points <i>(x<sub>1</sub>,y<sub>1</sub>)</i>, <i>(x<sub>2</sub>,y<sub>2</sub>)</i>, and <i>(x<sub>3</sub>,y<sub>3</sub>)</i>. The shoelace formula can also be used to find the areas of other polygons when their vertices are known. Another approach for a coordinate triangle is to use <a href="/wiki/Calculus" title="Calculus">calculus</a> to find the area.</li> <li>A <a href="/wiki/Simple_polygon" title="Simple polygon">simple polygon</a> constructed on a grid of equal-distanced points (i.e., points with <a href="/wiki/Integer" title="Integer">integer</a> coordinates) such that all the polygon's vertices are grid points: <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle i+{\frac {b}{2}}-1}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>i</mi> <mo>+</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mi>b</mi> <mn>2</mn> </mfrac> </mrow> <mo>&#x2212;<!-- − --></mo> <mn>1</mn> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle i+{\frac {b}{2}}-1}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/f6f6bf0fc9eaa8a4693b7dacc2a9e1a420dcedc6" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.838ex; width:9.644ex; height:5.343ex;" alt="{\displaystyle i+{\frac {b}{2}}-1}"></span>, where <i>i</i> is the number of grid points inside the polygon and <i>b</i> is the number of boundary points. This result is known as <a href="/wiki/Pick%27s_theorem" title="Pick&#39;s theorem">Pick's theorem</a>.<sup id="cite_ref-Pick_29-0" class="reference"><a href="#cite_note-Pick-29"><span class="cite-bracket">&#91;</span>29<span class="cite-bracket">&#93;</span></a></sup></li></ul> <div class="mw-heading mw-heading4"><h4 id="Area_in_calculus">Area in calculus</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=22" title="Edit section: Area in calculus"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Integral_as_region_under_curve.svg" class="mw-file-description"><img alt="A diagram showing the area between a given curve and the x-axis" src="//upload.wikimedia.org/wikipedia/commons/thumb/f/f2/Integral_as_region_under_curve.svg/220px-Integral_as_region_under_curve.svg.png" decoding="async" width="220" height="205" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/f2/Integral_as_region_under_curve.svg/330px-Integral_as_region_under_curve.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/f2/Integral_as_region_under_curve.svg/440px-Integral_as_region_under_curve.svg.png 2x" data-file-width="750" data-file-height="700" /></a><figcaption>Integration can be thought of as measuring the area under a curve, defined by <i>f</i>(<i>x</i>), between two points (here <i>a</i> and <i>b</i>).</figcaption></figure> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Areabetweentwographs.svg" class="mw-file-description"><img alt="A diagram showing the area between two functions" src="//upload.wikimedia.org/wikipedia/commons/thumb/f/f9/Areabetweentwographs.svg/220px-Areabetweentwographs.svg.png" decoding="async" width="220" height="198" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/f9/Areabetweentwographs.svg/330px-Areabetweentwographs.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/f9/Areabetweentwographs.svg/440px-Areabetweentwographs.svg.png 2x" data-file-width="1000" data-file-height="900" /></a><figcaption>The area between two graphs can be evaluated by calculating the difference between the integrals of the two functions</figcaption></figure> <ul><li>The area between a positive-valued curve and the horizontal axis, measured between two values <i>a</i> and <i>b</i> (b is defined as the larger of the two values) on the horizontal axis, is given by the integral from <i>a</i> to <i>b</i> of the function that represents the curve:<sup id="cite_ref-MathWorld_1-4" class="reference"><a href="#cite_note-MathWorld-1"><span class="cite-bracket">&#91;</span>1<span class="cite-bracket">&#93;</span></a></sup></li></ul> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A=\int _{a}^{b}f(x)\,dx.}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <msubsup> <mo>&#x222B;<!-- ∫ --></mo> <mrow class="MJX-TeXAtom-ORD"> <mi>a</mi> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mi>b</mi> </mrow> </msubsup> <mi>f</mi> <mo stretchy="false">(</mo> <mi>x</mi> <mo stretchy="false">)</mo> <mspace width="thinmathspace" /> <mi>d</mi> <mi>x</mi> <mo>.</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A=\int _{a}^{b}f(x)\,dx.}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/7c7fde7f01e5a0537613d14280b7811329b3c383" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.338ex; width:16.628ex; height:6.343ex;" alt="{\displaystyle A=\int _{a}^{b}f(x)\,dx.}"></span></dd></dl> <ul><li>The area between the <a href="/wiki/Graph_of_a_function" title="Graph of a function">graphs</a> of two functions is <a href="/wiki/Equality_(mathematics)" title="Equality (mathematics)">equal</a> to the <a href="/wiki/Integral" title="Integral">integral</a> of one <a href="/wiki/Function_(mathematics)" title="Function (mathematics)">function</a>, <i>f</i>(<i>x</i>), <a href="/wiki/Subtraction" title="Subtraction">minus</a> the integral of the other function, <i>g</i>(<i>x</i>):</li></ul> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A=\int _{a}^{b}(f(x)-g(x))\,dx,}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <msubsup> <mo>&#x222B;<!-- ∫ --></mo> <mrow class="MJX-TeXAtom-ORD"> <mi>a</mi> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mi>b</mi> </mrow> </msubsup> <mo stretchy="false">(</mo> <mi>f</mi> <mo stretchy="false">(</mo> <mi>x</mi> <mo stretchy="false">)</mo> <mo>&#x2212;<!-- − --></mo> <mi>g</mi> <mo stretchy="false">(</mo> <mi>x</mi> <mo stretchy="false">)</mo> <mo stretchy="false">)</mo> <mspace width="thinmathspace" /> <mi>d</mi> <mi>x</mi> <mo>,</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A=\int _{a}^{b}(f(x)-g(x))\,dx,}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/f7ba0f682fd365a15c175a3e2752970178d09edb" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.338ex; width:25.145ex; height:6.343ex;" alt="{\displaystyle A=\int _{a}^{b}(f(x)-g(x))\,dx,}"></span> where <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle f(x)}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>f</mi> <mo stretchy="false">(</mo> <mi>x</mi> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle f(x)}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/202945cce41ecebb6f643f31d119c514bec7a074" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:4.418ex; height:2.843ex;" alt="{\displaystyle f(x)}"></span> is the curve with the greater y-value.</dd></dl> <ul><li>An area bounded by a function <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle r=r(\theta )}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>r</mi> <mo>=</mo> <mi>r</mi> <mo stretchy="false">(</mo> <mi>&#x03B8;<!-- θ --></mi> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle r=r(\theta )}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/979c97f7e8c52e8ee26aa2e5ccd517cc76e31508" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:8.096ex; height:2.843ex;" alt="{\displaystyle r=r(\theta )}"></span> expressed in <a href="/wiki/Polar_coordinates" class="mw-redirect" title="Polar coordinates">polar coordinates</a> is:<sup id="cite_ref-MathWorld_1-5" class="reference"><a href="#cite_note-MathWorld-1"><span class="cite-bracket">&#91;</span>1<span class="cite-bracket">&#93;</span></a></sup></li></ul> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A={1 \over 2}\int r^{2}\,d\theta .}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mn>1</mn> <mn>2</mn> </mfrac> </mrow> <mo>&#x222B;<!-- ∫ --></mo> <msup> <mi>r</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mspace width="thinmathspace" /> <mi>d</mi> <mi>&#x03B8;<!-- θ --></mi> <mo>.</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A={1 \over 2}\int r^{2}\,d\theta .}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/e9ceec9961f3bfb4a2e5edfe77b4465adff35c37" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.338ex; width:15.251ex; height:5.676ex;" alt="{\displaystyle A={1 \over 2}\int r^{2}\,d\theta .}"></span></dd></dl> <ul><li>The area enclosed by a <a href="/wiki/Parametric_curve" class="mw-redirect" title="Parametric curve">parametric curve</a> <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\vec {u}}(t)=(x(t),y(t))}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mrow class="MJX-TeXAtom-ORD"> <mrow class="MJX-TeXAtom-ORD"> <mover> <mi>u</mi> <mo stretchy="false">&#x2192;<!-- → --></mo> </mover> </mrow> </mrow> <mo stretchy="false">(</mo> <mi>t</mi> <mo stretchy="false">)</mo> <mo>=</mo> <mo stretchy="false">(</mo> <mi>x</mi> <mo stretchy="false">(</mo> <mi>t</mi> <mo stretchy="false">)</mo> <mo>,</mo> <mi>y</mi> <mo stretchy="false">(</mo> <mi>t</mi> <mo stretchy="false">)</mo> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle {\vec {u}}(t)=(x(t),y(t))}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/60fca3145cbdd2d5c7ecfefa8e07a8041e39c449" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:17.703ex; height:2.843ex;" alt="{\displaystyle {\vec {u}}(t)=(x(t),y(t))}"></span> with endpoints <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\vec {u}}(t_{0})={\vec {u}}(t_{1})}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mrow class="MJX-TeXAtom-ORD"> <mrow class="MJX-TeXAtom-ORD"> <mover> <mi>u</mi> <mo stretchy="false">&#x2192;<!-- → --></mo> </mover> </mrow> </mrow> <mo stretchy="false">(</mo> <msub> <mi>t</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>0</mn> </mrow> </msub> <mo stretchy="false">)</mo> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mrow class="MJX-TeXAtom-ORD"> <mover> <mi>u</mi> <mo stretchy="false">&#x2192;<!-- → --></mo> </mover> </mrow> </mrow> <mo stretchy="false">(</mo> <msub> <mi>t</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>1</mn> </mrow> </msub> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle {\vec {u}}(t_{0})={\vec {u}}(t_{1})}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/eb8b51a1236ada19d3e70d976b6d617158edfadb" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:13.164ex; height:2.843ex;" alt="{\displaystyle {\vec {u}}(t_{0})={\vec {u}}(t_{1})}"></span> is given by the <a href="/wiki/Line_integral" title="Line integral">line integrals</a>:</li></ul> <dl><dd><dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \oint _{t_{0}}^{t_{1}}x{\dot {y}}\,dt=-\oint _{t_{0}}^{t_{1}}y{\dot {x}}\,dt={1 \over 2}\oint _{t_{0}}^{t_{1}}(x{\dot {y}}-y{\dot {x}})\,dt}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msubsup> <mo>&#x222E;<!-- ∮ --></mo> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>t</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>0</mn> </mrow> </msub> </mrow> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>t</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>1</mn> </mrow> </msub> </mrow> </msubsup> <mi>x</mi> <mrow class="MJX-TeXAtom-ORD"> <mrow class="MJX-TeXAtom-ORD"> <mover> <mi>y</mi> <mo>&#x02D9;<!-- ˙ --></mo> </mover> </mrow> </mrow> <mspace width="thinmathspace" /> <mi>d</mi> <mi>t</mi> <mo>=</mo> <mo>&#x2212;<!-- − --></mo> <msubsup> <mo>&#x222E;<!-- ∮ --></mo> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>t</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>0</mn> </mrow> </msub> </mrow> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>t</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>1</mn> </mrow> </msub> </mrow> </msubsup> <mi>y</mi> <mrow class="MJX-TeXAtom-ORD"> <mrow class="MJX-TeXAtom-ORD"> <mover> <mi>x</mi> <mo>&#x02D9;<!-- ˙ --></mo> </mover> </mrow> </mrow> <mspace width="thinmathspace" /> <mi>d</mi> <mi>t</mi> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mn>1</mn> <mn>2</mn> </mfrac> </mrow> <msubsup> <mo>&#x222E;<!-- ∮ --></mo> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>t</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>0</mn> </mrow> </msub> </mrow> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>t</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>1</mn> </mrow> </msub> </mrow> </msubsup> <mo stretchy="false">(</mo> <mi>x</mi> <mrow class="MJX-TeXAtom-ORD"> <mrow class="MJX-TeXAtom-ORD"> <mover> <mi>y</mi> <mo>&#x02D9;<!-- ˙ --></mo> </mover> </mrow> </mrow> <mo>&#x2212;<!-- − --></mo> <mi>y</mi> <mrow class="MJX-TeXAtom-ORD"> <mrow class="MJX-TeXAtom-ORD"> <mover> <mi>x</mi> <mo>&#x02D9;<!-- ˙ --></mo> </mover> </mrow> </mrow> <mo stretchy="false">)</mo> <mspace width="thinmathspace" /> <mi>d</mi> <mi>t</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \oint _{t_{0}}^{t_{1}}x{\dot {y}}\,dt=-\oint _{t_{0}}^{t_{1}}y{\dot {x}}\,dt={1 \over 2}\oint _{t_{0}}^{t_{1}}(x{\dot {y}}-y{\dot {x}})\,dt}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/940fad5094a1ce067667a15559feac98c0f02d5a" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.671ex; width:46.129ex; height:6.509ex;" alt="{\displaystyle \oint _{t_{0}}^{t_{1}}x{\dot {y}}\,dt=-\oint _{t_{0}}^{t_{1}}y{\dot {x}}\,dt={1 \over 2}\oint _{t_{0}}^{t_{1}}(x{\dot {y}}-y{\dot {x}})\,dt}"></span></dd></dl></dd> <dd>or the <i>z</i>-component of <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {1 \over 2}\oint _{t_{0}}^{t_{1}}{\vec {u}}\times {\dot {\vec {u}}}\,dt.}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mn>1</mn> <mn>2</mn> </mfrac> </mrow> <msubsup> <mo>&#x222E;<!-- ∮ --></mo> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>t</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>0</mn> </mrow> </msub> </mrow> <mrow class="MJX-TeXAtom-ORD"> <msub> <mi>t</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>1</mn> </mrow> </msub> </mrow> </msubsup> <mrow class="MJX-TeXAtom-ORD"> <mrow class="MJX-TeXAtom-ORD"> <mover> <mi>u</mi> <mo stretchy="false">&#x2192;<!-- → --></mo> </mover> </mrow> </mrow> <mo>&#x00D7;<!-- × --></mo> <mrow class="MJX-TeXAtom-ORD"> <mrow class="MJX-TeXAtom-ORD"> <mover> <mrow class="MJX-TeXAtom-ORD"> <mover> <mi>u</mi> <mo stretchy="false">&#x2192;<!-- → --></mo> </mover> </mrow> <mo>&#x02D9;<!-- ˙ --></mo> </mover> </mrow> </mrow> <mspace width="thinmathspace" /> <mi>d</mi> <mi>t</mi> <mo>.</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle {1 \over 2}\oint _{t_{0}}^{t_{1}}{\vec {u}}\times {\dot {\vec {u}}}\,dt.}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/ce6bf91b1745a4a27fe07a8b76f66324fb212233" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.671ex; width:15.484ex; height:6.509ex;" alt="{\displaystyle {1 \over 2}\oint _{t_{0}}^{t_{1}}{\vec {u}}\times {\dot {\vec {u}}}\,dt.}"></span></dd></dl></dd> <dd>(For details, see <a href="/wiki/Green%27s_theorem#Area_calculation" title="Green&#39;s theorem">Green's theorem §&#160;Area calculation</a>.) This is the principle of the <a href="/wiki/Planimeter" title="Planimeter">planimeter</a> mechanical device.</dd></dl> <div class="mw-heading mw-heading4"><h4 id="Bounded_area_between_two_quadratic_functions">Bounded area between two quadratic functions</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=23" title="Edit section: Bounded area between two quadratic functions"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>To find the bounded area between two <a href="/wiki/Quadratic_function" title="Quadratic function">quadratic functions</a>, we first subtract one from the other, writing the difference as <span class="mwe-math-element"><span class="mwe-math-mathml-display mwe-math-mathml-a11y" style="display: none;"><math display="block" xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle f(x)-g(x)=ax^{2}+bx+c=a(x-\alpha )(x-\beta )}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>f</mi> <mo stretchy="false">(</mo> <mi>x</mi> <mo stretchy="false">)</mo> <mo>&#x2212;<!-- − --></mo> <mi>g</mi> <mo stretchy="false">(</mo> <mi>x</mi> <mo stretchy="false">)</mo> <mo>=</mo> <mi>a</mi> <msup> <mi>x</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mo>+</mo> <mi>b</mi> <mi>x</mi> <mo>+</mo> <mi>c</mi> <mo>=</mo> <mi>a</mi> <mo stretchy="false">(</mo> <mi>x</mi> <mo>&#x2212;<!-- − --></mo> <mi>&#x03B1;<!-- α --></mi> <mo stretchy="false">)</mo> <mo stretchy="false">(</mo> <mi>x</mi> <mo>&#x2212;<!-- − --></mo> <mi>&#x03B2;<!-- β --></mi> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle f(x)-g(x)=ax^{2}+bx+c=a(x-\alpha )(x-\beta )}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/0db282d248f9398e0a6fbec8fe342148ba41a4a6" class="mwe-math-fallback-image-display mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:46.347ex; height:3.176ex;" alt="{\displaystyle f(x)-g(x)=ax^{2}+bx+c=a(x-\alpha )(x-\beta )}"></span> where <i>f</i>(<i>x</i>) is the quadratic upper bound and <i>g</i>(<i>x</i>) is the quadratic lower bound. By the area integral formulas above and <a href="/wiki/Vieta%27s_formulas" title="Vieta&#39;s formulas">Vieta's formula</a>, we can obtain that<sup id="cite_ref-30" class="reference"><a href="#cite_note-30"><span class="cite-bracket">&#91;</span>30<span class="cite-bracket">&#93;</span></a></sup><sup id="cite_ref-31" class="reference"><a href="#cite_note-31"><span class="cite-bracket">&#91;</span>31<span class="cite-bracket">&#93;</span></a></sup> <span class="mwe-math-element"><span class="mwe-math-mathml-display mwe-math-mathml-a11y" style="display: none;"><math display="block" xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A={\frac {(b^{2}-4ac)^{3/2}}{6a^{2}}}={\frac {a}{6}}(\beta -\alpha )^{3},\qquad a\neq 0.}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mo stretchy="false">(</mo> <msup> <mi>b</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mo>&#x2212;<!-- − --></mo> <mn>4</mn> <mi>a</mi> <mi>c</mi> <msup> <mo stretchy="false">)</mo> <mrow class="MJX-TeXAtom-ORD"> <mn>3</mn> <mrow class="MJX-TeXAtom-ORD"> <mo>/</mo> </mrow> <mn>2</mn> </mrow> </msup> </mrow> <mrow> <mn>6</mn> <msup> <mi>a</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> </mrow> </mfrac> </mrow> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mi>a</mi> <mn>6</mn> </mfrac> </mrow> <mo stretchy="false">(</mo> <mi>&#x03B2;<!-- β --></mi> <mo>&#x2212;<!-- − --></mo> <mi>&#x03B1;<!-- α --></mi> <msup> <mo stretchy="false">)</mo> <mrow class="MJX-TeXAtom-ORD"> <mn>3</mn> </mrow> </msup> <mo>,</mo> <mspace width="2em" /> <mi>a</mi> <mo>&#x2260;<!-- ≠ --></mo> <mn>0.</mn> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A={\frac {(b^{2}-4ac)^{3/2}}{6a^{2}}}={\frac {a}{6}}(\beta -\alpha )^{3},\qquad a\neq 0.}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/6a3244866c46c29a0bb151501fc90f375a1ec3a2" class="mwe-math-fallback-image-display mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.171ex; width:43.981ex; height:6.343ex;" alt="{\displaystyle A={\frac {(b^{2}-4ac)^{3/2}}{6a^{2}}}={\frac {a}{6}}(\beta -\alpha )^{3},\qquad a\neq 0.}"></span> The above remains valid if one of the bounding functions is linear instead of quadratic. </p> <div class="mw-heading mw-heading4"><h4 id="Surface_area_of_3-dimensional_figures">Surface area of 3-dimensional figures</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=24" title="Edit section: Surface area of 3-dimensional figures"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Cone" title="Cone">Cone</a>:<sup id="cite_ref-MathWorldCone_32-0" class="reference"><a href="#cite_note-MathWorldCone-32"><span class="cite-bracket">&#91;</span>32<span class="cite-bracket">&#93;</span></a></sup> <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \pi r\left(r+{\sqrt {r^{2}+h^{2}}}\right)}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>&#x03C0;<!-- π --></mi> <mi>r</mi> <mrow> <mo>(</mo> <mrow> <mi>r</mi> <mo>+</mo> <mrow class="MJX-TeXAtom-ORD"> <msqrt> <msup> <mi>r</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mo>+</mo> <msup> <mi>h</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> </msqrt> </mrow> </mrow> <mo>)</mo> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \pi r\left(r+{\sqrt {r^{2}+h^{2}}}\right)}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/41aca8f13a1e2996128c0ae640d7261682edf793" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.838ex; width:19.093ex; height:4.843ex;" alt="{\displaystyle \pi r\left(r+{\sqrt {r^{2}+h^{2}}}\right)}"></span>, where <i>r</i> is the radius of the circular base, and <i>h</i> is the height. That can also be rewritten as <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \pi r^{2}+\pi rl}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>&#x03C0;<!-- π --></mi> <msup> <mi>r</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mo>+</mo> <mi>&#x03C0;<!-- π --></mi> <mi>r</mi> <mi>l</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \pi r^{2}+\pi rl}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/9939e45942874b1579592e41aacbe316226bad99" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.505ex; width:9.349ex; height:2.843ex;" alt="{\displaystyle \pi r^{2}+\pi rl}"></span><sup id="cite_ref-MathWorldCone_32-1" class="reference"><a href="#cite_note-MathWorldCone-32"><span class="cite-bracket">&#91;</span>32<span class="cite-bracket">&#93;</span></a></sup> or <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \pi r(r+l)\,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>&#x03C0;<!-- π --></mi> <mi>r</mi> <mo stretchy="false">(</mo> <mi>r</mi> <mo>+</mo> <mi>l</mi> <mo stretchy="false">)</mo> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \pi r(r+l)\,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/0eda1165be2830dc4647cd6d3ce53b7aa6d345ab" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; margin-right: -0.387ex; width:9.159ex; height:2.843ex;" alt="{\displaystyle \pi r(r+l)\,\!}"></span> where <i>r</i> is the radius and <i>l</i> is the slant height of the cone. <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \pi r^{2}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>&#x03C0;<!-- π --></mi> <msup> <mi>r</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \pi r^{2}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/cd37db3982ad4e1157dcf8ddbfb280e7bae3b192" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:3.435ex; height:2.676ex;" alt="{\displaystyle \pi r^{2}}"></span> is the base area while <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \pi rl}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>&#x03C0;<!-- π --></mi> <mi>r</mi> <mi>l</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \pi rl}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/150bc25be0060c8e640e924e29242b9a1a8af64c" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:3.074ex; height:2.176ex;" alt="{\displaystyle \pi rl}"></span> is the lateral surface area of the cone.<sup id="cite_ref-MathWorldCone_32-2" class="reference"><a href="#cite_note-MathWorldCone-32"><span class="cite-bracket">&#91;</span>32<span class="cite-bracket">&#93;</span></a></sup></li> <li><a href="/wiki/Cube" title="Cube">Cube</a>: <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle 6s^{2}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mn>6</mn> <msup> <mi>s</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle 6s^{2}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/14c8686e0f2659ed3e427883b9863e411b8832d0" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:3.307ex; height:2.676ex;" alt="{\displaystyle 6s^{2}}"></span>, where <i>s</i> is the length of an edge.<sup id="cite_ref-MathWorldSurfaceArea_6-2" class="reference"><a href="#cite_note-MathWorldSurfaceArea-6"><span class="cite-bracket">&#91;</span>6<span class="cite-bracket">&#93;</span></a></sup></li> <li><a href="/wiki/Cylinder" title="Cylinder">Cylinder</a>: <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle 2\pi r(r+h)}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mn>2</mn> <mi>&#x03C0;<!-- π --></mi> <mi>r</mi> <mo stretchy="false">(</mo> <mi>r</mi> <mo>+</mo> <mi>h</mi> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle 2\pi r(r+h)}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/540fd341370c845484ed38751872e27df0219682" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:10.58ex; height:2.843ex;" alt="{\displaystyle 2\pi r(r+h)}"></span>, where <i>r</i> is the radius of a base and <i>h</i> is the height. The <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle 2\pi r}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mn>2</mn> <mi>&#x03C0;<!-- π --></mi> <mi>r</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle 2\pi r}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/71e811131a9c6c5f45e6657e0fc506e7e2a37f06" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:3.543ex; height:2.176ex;" alt="{\displaystyle 2\pi r}"></span> can also be rewritten as <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \pi d}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>&#x03C0;<!-- π --></mi> <mi>d</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \pi d}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/3cc818436da025a58d10638dc12c92ad1c4e3ced" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:2.548ex; height:2.176ex;" alt="{\displaystyle \pi d}"></span>, where <i>d</i> is the diameter.</li> <li><a href="/wiki/Prism_(geometry)" title="Prism (geometry)">Prism</a>: <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle 2B+Ph}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mn>2</mn> <mi>B</mi> <mo>+</mo> <mi>P</mi> <mi>h</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle 2B+Ph}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/881aa43d6a2ffa10f58717ca57ba2c8125f0d1c9" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.505ex; width:8.851ex; height:2.343ex;" alt="{\displaystyle 2B+Ph}"></span>, where <i>B</i> is the area of a base, <i>P</i> is the perimeter of a base, and <i>h</i> is the height of the prism.</li> <li><a href="/wiki/Pyramid_(geometry)" title="Pyramid (geometry)">pyramid</a>: <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle B+{\frac {PL}{2}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>B</mi> <mo>+</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mi>P</mi> <mi>L</mi> </mrow> <mn>2</mn> </mfrac> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle B+{\frac {PL}{2}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/f3d5cac9cbaea2d315ce42caf71d241056c043b1" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.838ex; width:8.769ex; height:5.176ex;" alt="{\displaystyle B+{\frac {PL}{2}}}"></span>, where <i>B</i> is the area of the base, <i>P</i> is the perimeter of the base, and <i>L</i> is the length of the slant.</li> <li><a href="/wiki/Rectangular_prism" class="mw-redirect" title="Rectangular prism">Rectangular prism</a>: <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle 2(\ell w+\ell h+wh)}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mn>2</mn> <mo stretchy="false">(</mo> <mi>&#x2113;<!-- ℓ --></mi> <mi>w</mi> <mo>+</mo> <mi>&#x2113;<!-- ℓ --></mi> <mi>h</mi> <mo>+</mo> <mi>w</mi> <mi>h</mi> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle 2(\ell w+\ell h+wh)}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/d7db04a449659be887d57e8c8d175a0bc6f720e2" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:16.598ex; height:2.843ex;" alt="{\displaystyle 2(\ell w+\ell h+wh)}"></span>, where <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \ell }"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>&#x2113;<!-- ℓ --></mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \ell }</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/f066e981e530bacc07efc6a10fa82deee985929e" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:0.97ex; height:2.176ex;" alt="{\displaystyle \ell }"></span> is the length, <i>w</i> is the width, and <i>h</i> is the height.</li></ul> <div class="mw-heading mw-heading4"><h4 id="General_formula_for_surface_area">General formula for surface area</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=25" title="Edit section: General formula for surface area"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The general formula for the surface area of the graph of a continuously differentiable function <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle z=f(x,y),}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>z</mi> <mo>=</mo> <mi>f</mi> <mo stretchy="false">(</mo> <mi>x</mi> <mo>,</mo> <mi>y</mi> <mo stretchy="false">)</mo> <mo>,</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle z=f(x,y),}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/1269bfd7a8dbf5a109363ce2a7992efdf8e406a9" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:11.44ex; height:2.843ex;" alt="{\displaystyle z=f(x,y),}"></span> where <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle (x,y)\in D\subset \mathbb {R} ^{2}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mo stretchy="false">(</mo> <mi>x</mi> <mo>,</mo> <mi>y</mi> <mo stretchy="false">)</mo> <mo>&#x2208;<!-- ∈ --></mo> <mi>D</mi> <mo>&#x2282;<!-- ⊂ --></mo> <msup> <mrow class="MJX-TeXAtom-ORD"> <mi mathvariant="double-struck">R</mi> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle (x,y)\in D\subset \mathbb {R} ^{2}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/889ab97d6b3f931120e277a925164d57cda96072" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:15.924ex; height:3.176ex;" alt="{\displaystyle (x,y)\in D\subset \mathbb {R} ^{2}}"></span> and <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle D}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>D</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle D}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/f34a0c600395e5d4345287e21fb26efd386990e6" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.924ex; height:2.176ex;" alt="{\displaystyle D}"></span> is a region in the xy-plane with the smooth boundary: </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A=\iint _{D}{\sqrt {\left({\frac {\partial f}{\partial x}}\right)^{2}+\left({\frac {\partial f}{\partial y}}\right)^{2}+1}}\,dx\,dy.}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <msub> <mo>&#x222C;<!-- ∬ --></mo> <mrow class="MJX-TeXAtom-ORD"> <mi>D</mi> </mrow> </msub> <mrow class="MJX-TeXAtom-ORD"> <msqrt> <msup> <mrow> <mo>(</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mi mathvariant="normal">&#x2202;<!-- ∂ --></mi> <mi>f</mi> </mrow> <mrow> <mi mathvariant="normal">&#x2202;<!-- ∂ --></mi> <mi>x</mi> </mrow> </mfrac> </mrow> <mo>)</mo> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mo>+</mo> <msup> <mrow> <mo>(</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mi mathvariant="normal">&#x2202;<!-- ∂ --></mi> <mi>f</mi> </mrow> <mrow> <mi mathvariant="normal">&#x2202;<!-- ∂ --></mi> <mi>y</mi> </mrow> </mfrac> </mrow> <mo>)</mo> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mo>+</mo> <mn>1</mn> </msqrt> </mrow> <mspace width="thinmathspace" /> <mi>d</mi> <mi>x</mi> <mspace width="thinmathspace" /> <mi>d</mi> <mi>y</mi> <mo>.</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A=\iint _{D}{\sqrt {\left({\frac {\partial f}{\partial x}}\right)^{2}+\left({\frac {\partial f}{\partial y}}\right)^{2}+1}}\,dx\,dy.}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/8c1ccc930568eb5c289a5a2e6a29c774b6138e28" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -3.005ex; width:40.713ex; height:7.676ex;" alt="{\displaystyle A=\iint _{D}{\sqrt {\left({\frac {\partial f}{\partial x}}\right)^{2}+\left({\frac {\partial f}{\partial y}}\right)^{2}+1}}\,dx\,dy.}"></span></dd></dl> <p>An even more general formula for the area of the graph of a <a href="/wiki/Parametric_surface" title="Parametric surface">parametric surface</a> in the vector form <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \mathbf {r} =\mathbf {r} (u,v),}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mrow class="MJX-TeXAtom-ORD"> <mi mathvariant="bold">r</mi> </mrow> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mi mathvariant="bold">r</mi> </mrow> <mo stretchy="false">(</mo> <mi>u</mi> <mo>,</mo> <mi>v</mi> <mo stretchy="false">)</mo> <mo>,</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \mathbf {r} =\mathbf {r} (u,v),}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/6aeec617173611dac8fc72db0dff05aa533de232" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:11.25ex; height:2.843ex;" alt="{\displaystyle \mathbf {r} =\mathbf {r} (u,v),}"></span> where <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \mathbf {r} }"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mrow class="MJX-TeXAtom-ORD"> <mi mathvariant="bold">r</mi> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \mathbf {r} }</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/eca0f46511c4c986c48b254073732c0bd98ae0c1" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.102ex; height:1.676ex;" alt="{\displaystyle \mathbf {r} }"></span> is a continuously differentiable vector function of <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle (u,v)\in D\subset \mathbb {R} ^{2}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mo stretchy="false">(</mo> <mi>u</mi> <mo>,</mo> <mi>v</mi> <mo stretchy="false">)</mo> <mo>&#x2208;<!-- ∈ --></mo> <mi>D</mi> <mo>&#x2282;<!-- ⊂ --></mo> <msup> <mrow class="MJX-TeXAtom-ORD"> <mi mathvariant="double-struck">R</mi> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle (u,v)\in D\subset \mathbb {R} ^{2}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/840754272f6c3d17618fe2a2ca80697700dc9adc" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:15.896ex; height:3.176ex;" alt="{\displaystyle (u,v)\in D\subset \mathbb {R} ^{2}}"></span> is:<sup id="cite_ref-doCarmo_8-1" class="reference"><a href="#cite_note-doCarmo-8"><span class="cite-bracket">&#91;</span>8<span class="cite-bracket">&#93;</span></a></sup> </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A=\iint _{D}\left|{\frac {\partial \mathbf {r} }{\partial u}}\times {\frac {\partial \mathbf {r} }{\partial v}}\right|\,du\,dv.}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <msub> <mo>&#x222C;<!-- ∬ --></mo> <mrow class="MJX-TeXAtom-ORD"> <mi>D</mi> </mrow> </msub> <mrow> <mo>|</mo> <mrow> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mi mathvariant="normal">&#x2202;<!-- ∂ --></mi> <mrow class="MJX-TeXAtom-ORD"> <mi mathvariant="bold">r</mi> </mrow> </mrow> <mrow> <mi mathvariant="normal">&#x2202;<!-- ∂ --></mi> <mi>u</mi> </mrow> </mfrac> </mrow> <mo>&#x00D7;<!-- × --></mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mi mathvariant="normal">&#x2202;<!-- ∂ --></mi> <mrow class="MJX-TeXAtom-ORD"> <mi mathvariant="bold">r</mi> </mrow> </mrow> <mrow> <mi mathvariant="normal">&#x2202;<!-- ∂ --></mi> <mi>v</mi> </mrow> </mfrac> </mrow> </mrow> <mo>|</mo> </mrow> <mspace width="thinmathspace" /> <mi>d</mi> <mi>u</mi> <mspace width="thinmathspace" /> <mi>d</mi> <mi>v</mi> <mo>.</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A=\iint _{D}\left|{\frac {\partial \mathbf {r} }{\partial u}}\times {\frac {\partial \mathbf {r} }{\partial v}}\right|\,du\,dv.}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/9d0b4024b8e933d55893aad41806b2e8bedf6ae9" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.338ex; width:26.937ex; height:5.843ex;" alt="{\displaystyle A=\iint _{D}\left|{\frac {\partial \mathbf {r} }{\partial u}}\times {\frac {\partial \mathbf {r} }{\partial v}}\right|\,du\,dv.}"></span></dd></dl> <div class="mw-heading mw-heading3"><h3 id="List_of_formulas">List of formulas</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=26" title="Edit section: List of formulas"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <table class="wikitable"> <caption>Additional common formulas for area: </caption> <tbody><tr> <th>Shape </th> <th>Formula </th> <th>Variables </th></tr> <tr> <td><a href="/wiki/Square" title="Square">Square</a> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A=s^{2}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <msup> <mi>s</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A=s^{2}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/1607109864e43a307cc541ff06b73a7bfe423500" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:6.986ex; height:2.676ex;" alt="{\displaystyle A=s^{2}}"></span> </td> <td><span typeof="mw:File"><a href="/wiki/File:Simple_square_with_sides_marked.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b6/Simple_square_with_sides_marked.svg/120px-Simple_square_with_sides_marked.svg.png" decoding="async" width="120" height="120" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b6/Simple_square_with_sides_marked.svg/180px-Simple_square_with_sides_marked.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b6/Simple_square_with_sides_marked.svg/240px-Simple_square_with_sides_marked.svg.png 2x" data-file-width="120" data-file-height="120" /></a></span> </td></tr> <tr> <td><a href="/wiki/Rectangle" title="Rectangle">Rectangle</a> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A=ab}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mi>a</mi> <mi>b</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A=ab}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/b0d1d98eb0f7365f44de12cd8d7198161ebb1a48" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:7.069ex; height:2.176ex;" alt="{\displaystyle A=ab}"></span> </td> <td><span typeof="mw:File"><a href="/wiki/File:Rechteck-ab.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/7/7e/Rechteck-ab.svg/120px-Rechteck-ab.svg.png" decoding="async" width="120" height="69" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/7e/Rechteck-ab.svg/180px-Rechteck-ab.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/7e/Rechteck-ab.svg/240px-Rechteck-ab.svg.png 2x" data-file-width="126" data-file-height="72" /></a></span> </td></tr> <tr> <td><a href="/wiki/Triangle" title="Triangle">Triangle</a> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A={\frac {1}{2}}bh\,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mn>1</mn> <mn>2</mn> </mfrac> </mrow> <mi>b</mi> <mi>h</mi> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A={\frac {1}{2}}bh\,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/68d797f5563af8f5d34ea0bb8713dcee923f8836" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.838ex; margin-right: -0.387ex; width:9.564ex; height:5.176ex;" alt="{\displaystyle A={\frac {1}{2}}bh\,\!}"></span> </td> <td><span typeof="mw:File"><a href="/wiki/File:Dreieck-allg-bh.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/9/93/Dreieck-allg-bh.svg/100px-Dreieck-allg-bh.svg.png" decoding="async" width="100" height="88" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/93/Dreieck-allg-bh.svg/150px-Dreieck-allg-bh.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/93/Dreieck-allg-bh.svg/200px-Dreieck-allg-bh.svg.png 2x" data-file-width="144" data-file-height="126" /></a></span> </td></tr> <tr> <td><a href="/wiki/Triangle" title="Triangle">Triangle</a> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A={\frac {1}{2}}ab\sin(\gamma )\,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mn>1</mn> <mn>2</mn> </mfrac> </mrow> <mi>a</mi> <mi>b</mi> <mi>sin</mi> <mo>&#x2061;<!-- ⁡ --></mo> <mo stretchy="false">(</mo> <mi>&#x03B3;<!-- γ --></mi> <mo stretchy="false">)</mo> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A={\frac {1}{2}}ab\sin(\gamma )\,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/91134999becbb6016f19e13d63c7eba807007b37" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.838ex; margin-right: -0.387ex; width:15.769ex; height:5.176ex;" alt="{\displaystyle A={\frac {1}{2}}ab\sin(\gamma )\,\!}"></span> </td> <td><span typeof="mw:File"><a href="/wiki/File:Dreieck-allg-w.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/2/2f/Dreieck-allg-w.svg/100px-Dreieck-allg-w.svg.png" decoding="async" width="100" height="88" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/2f/Dreieck-allg-w.svg/150px-Dreieck-allg-w.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/2f/Dreieck-allg-w.svg/200px-Dreieck-allg-w.svg.png 2x" data-file-width="144" data-file-height="126" /></a></span> </td></tr> <tr> <td><a href="/wiki/Triangle" title="Triangle">Triangle</a><br /> <p>(<a href="/wiki/Heron%27s_formula" title="Heron&#39;s formula">Heron's formula</a>) </p> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A={\sqrt {s(s-a)(s-b)(s-c)}}\,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <msqrt> <mi>s</mi> <mo stretchy="false">(</mo> <mi>s</mi> <mo>&#x2212;<!-- − --></mo> <mi>a</mi> <mo stretchy="false">)</mo> <mo stretchy="false">(</mo> <mi>s</mi> <mo>&#x2212;<!-- − --></mo> <mi>b</mi> <mo stretchy="false">)</mo> <mo stretchy="false">(</mo> <mi>s</mi> <mo>&#x2212;<!-- − --></mo> <mi>c</mi> <mo stretchy="false">)</mo> </msqrt> </mrow> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A={\sqrt {s(s-a)(s-b)(s-c)}}\,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/ce11654ff137a2f313184e36f20768b0890d3759" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.838ex; margin-right: -0.387ex; width:29.098ex; height:4.843ex;" alt="{\displaystyle A={\sqrt {s(s-a)(s-b)(s-c)}}\,\!}"></span> </td> <td><span typeof="mw:File"><a href="/wiki/File:Dreieck-allg.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/3/3c/Dreieck-allg.svg/100px-Dreieck-allg.svg.png" decoding="async" width="100" height="88" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/3c/Dreieck-allg.svg/150px-Dreieck-allg.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/3c/Dreieck-allg.svg/200px-Dreieck-allg.svg.png 2x" data-file-width="144" data-file-height="126" /></a></span> <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle s={\tfrac {1}{2}}(a+b+c)}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>s</mi> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="false" scriptlevel="0"> <mfrac> <mn>1</mn> <mn>2</mn> </mfrac> </mstyle> </mrow> <mo stretchy="false">(</mo> <mi>a</mi> <mo>+</mo> <mi>b</mi> <mo>+</mo> <mi>c</mi> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle s={\tfrac {1}{2}}(a+b+c)}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/ed2c4193212526a50585182f301e85e2f1cdfde8" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.171ex; width:16.571ex; height:3.509ex;" alt="{\displaystyle s={\tfrac {1}{2}}(a+b+c)}"></span> </td></tr> <tr> <td><a href="/wiki/Isosceles_triangle" title="Isosceles triangle">Isosceles triangle</a> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A={\frac {c}{4}}{\sqrt {4a^{2}-c^{2}}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mi>c</mi> <mn>4</mn> </mfrac> </mrow> <mrow class="MJX-TeXAtom-ORD"> <msqrt> <mn>4</mn> <msup> <mi>a</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mo>&#x2212;<!-- − --></mo> <msup> <mi>c</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> </msqrt> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A={\frac {c}{4}}{\sqrt {4a^{2}-c^{2}}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/8cdc3d444be871d87a9088601f933a9fcdf39733" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.838ex; width:17.512ex; height:4.676ex;" alt="{\displaystyle A={\frac {c}{4}}{\sqrt {4a^{2}-c^{2}}}}"></span> </td> <td><span typeof="mw:File"><a href="/wiki/File:Dreieck-gsch.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/1/12/Dreieck-gsch.svg/80px-Dreieck-gsch.svg.png" decoding="async" width="80" height="93" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/12/Dreieck-gsch.svg/120px-Dreieck-gsch.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/12/Dreieck-gsch.svg/160px-Dreieck-gsch.svg.png 2x" data-file-width="108" data-file-height="126" /></a></span> </td></tr> <tr> <td>Regular <a href="/wiki/Triangle" title="Triangle">triangle</a><br /> <p>(<a href="/wiki/Equilateral_triangle" title="Equilateral triangle">equilateral triangle</a>) </p> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A={\frac {\sqrt {3}}{4}}a^{2}\,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <msqrt> <mn>3</mn> </msqrt> <mn>4</mn> </mfrac> </mrow> <msup> <mi>a</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A={\frac {\sqrt {3}}{4}}a^{2}\,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/8109993210fe0425fe4949b7c8c8ce1faa1d48a5" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.838ex; margin-right: -0.387ex; width:11.447ex; height:5.843ex;" alt="{\displaystyle A={\frac {\sqrt {3}}{4}}a^{2}\,\!}"></span> </td> <td><span typeof="mw:File"><a href="/wiki/File:Dreieck-gseit.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/e/ee/Dreieck-gseit.svg/100px-Dreieck-gseit.svg.png" decoding="async" width="100" height="88" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/ee/Dreieck-gseit.svg/150px-Dreieck-gseit.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/ee/Dreieck-gseit.svg/200px-Dreieck-gseit.svg.png 2x" data-file-width="144" data-file-height="126" /></a></span> </td></tr> <tr> <td><a href="/wiki/Rhombus" title="Rhombus">Rhombus</a>/<a href="/wiki/Kite_(geometry)" title="Kite (geometry)">Kite</a> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A={\frac {1}{2}}de}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mn>1</mn> <mn>2</mn> </mfrac> </mrow> <mi>d</mi> <mi>e</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A={\frac {1}{2}}de}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/84d11afa99e38d284615d1e8110b0a5cb9701976" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.838ex; width:9.14ex; height:5.176ex;" alt="{\displaystyle A={\frac {1}{2}}de}"></span> </td> <td><span typeof="mw:File"><a href="/wiki/File:Raute-de.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/0/0b/Raute-de.svg/160px-Raute-de.svg.png" decoding="async" width="160" height="93" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/0/0b/Raute-de.svg/240px-Raute-de.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/0/0b/Raute-de.svg/320px-Raute-de.svg.png 2x" data-file-width="216" data-file-height="126" /></a></span> </td></tr> <tr> <td><a href="/wiki/Parallelogram" title="Parallelogram">Parallelogram</a> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A=ah_{a}\,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mi>a</mi> <msub> <mi>h</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>a</mi> </mrow> </msub> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A=ah_{a}\,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/1c33ad35df2d9f53110a71cba103a87797117227" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; margin-right: -0.387ex; width:8.899ex; height:2.509ex;" alt="{\displaystyle A=ah_{a}\,\!}"></span> </td> <td><span typeof="mw:File"><a href="/wiki/File:Parallelog-aha.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/4/4b/Parallelog-aha.svg/160px-Parallelog-aha.svg.png" decoding="async" width="160" height="71" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/4b/Parallelog-aha.svg/240px-Parallelog-aha.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/4b/Parallelog-aha.svg/320px-Parallelog-aha.svg.png 2x" data-file-width="162" data-file-height="72" /></a></span> </td></tr> <tr> <td><a href="/wiki/Trapezoid" title="Trapezoid">Trapezoid</a> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A={\frac {(a+c)h}{2}}\,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mo stretchy="false">(</mo> <mi>a</mi> <mo>+</mo> <mi>c</mi> <mo stretchy="false">)</mo> <mi>h</mi> </mrow> <mn>2</mn> </mfrac> </mrow> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A={\frac {(a+c)h}{2}}\,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/8db9433565e4c823948974baab1bb9a07d50a4ed" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.838ex; margin-right: -0.387ex; width:14.29ex; height:5.676ex;" alt="{\displaystyle A={\frac {(a+c)h}{2}}\,\!}"></span> </td> <td><span typeof="mw:File"><a href="/wiki/File:Trapez-abcdh.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/c1/Trapez-abcdh.svg/150px-Trapez-abcdh.svg.png" decoding="async" width="150" height="86" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/c1/Trapez-abcdh.svg/225px-Trapez-abcdh.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/c1/Trapez-abcdh.svg/300px-Trapez-abcdh.svg.png 2x" data-file-width="189" data-file-height="108" /></a></span> </td></tr> <tr> <td>Regular <a href="/wiki/Hexagon" title="Hexagon">hexagon</a> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A={\frac {3}{2}}{\sqrt {3}}a^{2}\,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mn>3</mn> <mn>2</mn> </mfrac> </mrow> <mrow class="MJX-TeXAtom-ORD"> <msqrt> <mn>3</mn> </msqrt> </mrow> <msup> <mi>a</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A={\frac {3}{2}}{\sqrt {3}}a^{2}\,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/7b1fa9f06cf4c87e28a98a62e42550951c222837" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.838ex; margin-right: -0.387ex; width:12.61ex; height:5.176ex;" alt="{\displaystyle A={\frac {3}{2}}{\sqrt {3}}a^{2}\,\!}"></span> </td> <td><span typeof="mw:File"><a href="/wiki/File:Hexagon-a.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/a/a5/Hexagon-a.svg/100px-Hexagon-a.svg.png" decoding="async" width="100" height="114" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/a5/Hexagon-a.svg/150px-Hexagon-a.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/a5/Hexagon-a.svg/200px-Hexagon-a.svg.png 2x" data-file-width="126" data-file-height="144" /></a></span> </td></tr> <tr> <td>Regular <a href="/wiki/Octagon" title="Octagon">octagon</a> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A=2(1+{\sqrt {2}})a^{2}\,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mn>2</mn> <mo stretchy="false">(</mo> <mn>1</mn> <mo>+</mo> <mrow class="MJX-TeXAtom-ORD"> <msqrt> <mn>2</mn> </msqrt> </mrow> <mo stretchy="false">)</mo> <msup> <mi>a</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A=2(1+{\sqrt {2}})a^{2}\,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/5e1d46f7e735047e5309c52b6f2d6fcb183a5cb8" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; margin-right: -0.387ex; width:17.586ex; height:3.176ex;" alt="{\displaystyle A=2(1+{\sqrt {2}})a^{2}\,\!}"></span> </td> <td><span typeof="mw:File"><a href="/wiki/File:Oktagon-a.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/6/6c/Oktagon-a.svg/120px-Oktagon-a.svg.png" decoding="async" width="120" height="120" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/6c/Oktagon-a.svg/180px-Oktagon-a.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/6c/Oktagon-a.svg/240px-Oktagon-a.svg.png 2x" data-file-width="180" data-file-height="180" /></a></span> </td></tr> <tr> <td><a href="/wiki/Regular_polygon" title="Regular polygon">Regular polygon</a><br /> <p>(<span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle n}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>n</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle n}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/a601995d55609f2d9f5e233e36fbe9ea26011b3b" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.395ex; height:1.676ex;" alt="{\displaystyle n}"></span> sides) </p> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A=n{\frac {ar}{2}}={\frac {pr}{2}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mi>n</mi> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mi>a</mi> <mi>r</mi> </mrow> <mn>2</mn> </mfrac> </mrow> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mi>p</mi> <mi>r</mi> </mrow> <mn>2</mn> </mfrac> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A=n{\frac {ar}{2}}={\frac {pr}{2}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/354b89a0f2e027b715f7457dbc20fa2c5066637c" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.838ex; width:15.504ex; height:4.843ex;" alt="{\displaystyle A=n{\frac {ar}{2}}={\frac {pr}{2}}}"></span><br /> <p><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \quad ={\tfrac {1}{4}}na^{2}\cot({\tfrac {\pi }{n}})}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mspace width="1em" /> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="false" scriptlevel="0"> <mfrac> <mn>1</mn> <mn>4</mn> </mfrac> </mstyle> </mrow> <mi>n</mi> <msup> <mi>a</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mi>cot</mi> <mo>&#x2061;<!-- ⁡ --></mo> <mo stretchy="false">(</mo> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="false" scriptlevel="0"> <mfrac> <mi>&#x03C0;<!-- π --></mi> <mi>n</mi> </mfrac> </mstyle> </mrow> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \quad ={\tfrac {1}{4}}na^{2}\cot({\tfrac {\pi }{n}})}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/c0a890b71c812186d1c7a7b00691f47d8894569e" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.171ex; width:17.231ex; height:3.509ex;" alt="{\displaystyle \quad ={\tfrac {1}{4}}na^{2}\cot({\tfrac {\pi }{n}})}"></span><br /> <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \quad =nr^{2}\tan({\tfrac {\pi }{n}})}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mspace width="1em" /> <mo>=</mo> <mi>n</mi> <msup> <mi>r</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mi>tan</mi> <mo>&#x2061;<!-- ⁡ --></mo> <mo stretchy="false">(</mo> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="false" scriptlevel="0"> <mfrac> <mi>&#x03C0;<!-- π --></mi> <mi>n</mi> </mfrac> </mstyle> </mrow> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \quad =nr^{2}\tan({\tfrac {\pi }{n}})}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/4fa0c6ff722626e412a1d61972be24dd8e1d3f5d" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:15.652ex; height:3.343ex;" alt="{\displaystyle \quad =nr^{2}\tan({\tfrac {\pi }{n}})}"></span><br /> <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \quad ={\tfrac {1}{4n}}p^{2}\cot({\tfrac {\pi }{n}})}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mspace width="1em" /> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="false" scriptlevel="0"> <mfrac> <mn>1</mn> <mrow> <mn>4</mn> <mi>n</mi> </mrow> </mfrac> </mstyle> </mrow> <msup> <mi>p</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mi>cot</mi> <mo>&#x2061;<!-- ⁡ --></mo> <mo stretchy="false">(</mo> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="false" scriptlevel="0"> <mfrac> <mi>&#x03C0;<!-- π --></mi> <mi>n</mi> </mfrac> </mstyle> </mrow> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \quad ={\tfrac {1}{4n}}p^{2}\cot({\tfrac {\pi }{n}})}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/b1792087716dc1ab272bda5419cb0085de55a1b9" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.338ex; width:16.762ex; height:3.676ex;" alt="{\displaystyle \quad ={\tfrac {1}{4n}}p^{2}\cot({\tfrac {\pi }{n}})}"></span><br /> <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \quad ={\tfrac {1}{2}}nR^{2}\sin({\tfrac {2\pi }{n}})\,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mspace width="1em" /> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="false" scriptlevel="0"> <mfrac> <mn>1</mn> <mn>2</mn> </mfrac> </mstyle> </mrow> <mi>n</mi> <msup> <mi>R</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mi>sin</mi> <mo>&#x2061;<!-- ⁡ --></mo> <mo stretchy="false">(</mo> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="false" scriptlevel="0"> <mfrac> <mrow> <mn>2</mn> <mi>&#x03C0;<!-- π --></mi> </mrow> <mi>n</mi> </mfrac> </mstyle> </mrow> <mo stretchy="false">)</mo> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \quad ={\tfrac {1}{2}}nR^{2}\sin({\tfrac {2\pi }{n}})\,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/9a3dde5ca35e56525e8de9aebce33d26affbd5d2" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.171ex; margin-right: -0.387ex; width:18.686ex; height:3.509ex;" alt="{\displaystyle \quad ={\tfrac {1}{2}}nR^{2}\sin({\tfrac {2\pi }{n}})\,\!}"></span> </p> </td> <td><figure class="mw-halign-left" typeof="mw:File"><a href="/wiki/File:Oktagon-a-r-R.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/2/20/Oktagon-a-r-R.svg/150px-Oktagon-a-r-R.svg.png" decoding="async" width="150" height="150" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/2/20/Oktagon-a-r-R.svg/225px-Oktagon-a-r-R.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/2/20/Oktagon-a-r-R.svg/300px-Oktagon-a-r-R.svg.png 2x" data-file-width="189" data-file-height="189" /></a><figcaption></figcaption></figure> <p><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle p=na\ }"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>p</mi> <mo>=</mo> <mi>n</mi> <mi>a</mi> <mtext>&#xA0;</mtext> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle p=na\ }</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/d8237110ed23490fd2d7cf587201703fc3d0a091" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; margin-left: -0.089ex; width:7.562ex; height:2.009ex;" alt="{\displaystyle p=na\ }"></span> (<a href="/wiki/Perimeter" title="Perimeter">perimeter</a>)<br /> <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle r={\tfrac {a}{2}}\cot({\tfrac {\pi }{n}}),}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>r</mi> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="false" scriptlevel="0"> <mfrac> <mi>a</mi> <mn>2</mn> </mfrac> </mstyle> </mrow> <mi>cot</mi> <mo>&#x2061;<!-- ⁡ --></mo> <mo stretchy="false">(</mo> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="false" scriptlevel="0"> <mfrac> <mi>&#x03C0;<!-- π --></mi> <mi>n</mi> </mfrac> </mstyle> </mrow> <mo stretchy="false">)</mo> <mo>,</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle r={\tfrac {a}{2}}\cot({\tfrac {\pi }{n}}),}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/86622d72f2ee710c3c4a45919c89fdb4fde835af" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.171ex; width:13.618ex; height:3.176ex;" alt="{\displaystyle r={\tfrac {a}{2}}\cot({\tfrac {\pi }{n}}),}"></span><br /> <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\tfrac {a}{2}}=r\tan({\tfrac {\pi }{n}})=R\sin({\tfrac {\pi }{n}})}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="false" scriptlevel="0"> <mfrac> <mi>a</mi> <mn>2</mn> </mfrac> </mstyle> </mrow> <mo>=</mo> <mi>r</mi> <mi>tan</mi> <mo>&#x2061;<!-- ⁡ --></mo> <mo stretchy="false">(</mo> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="false" scriptlevel="0"> <mfrac> <mi>&#x03C0;<!-- π --></mi> <mi>n</mi> </mfrac> </mstyle> </mrow> <mo stretchy="false">)</mo> <mo>=</mo> <mi>R</mi> <mi>sin</mi> <mo>&#x2061;<!-- ⁡ --></mo> <mo stretchy="false">(</mo> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="false" scriptlevel="0"> <mfrac> <mi>&#x03C0;<!-- π --></mi> <mi>n</mi> </mfrac> </mstyle> </mrow> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle {\tfrac {a}{2}}=r\tan({\tfrac {\pi }{n}})=R\sin({\tfrac {\pi }{n}})}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/027949269e1cadcd61be7bd9e9e4d9c2e91a1689" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.171ex; width:24.968ex; height:3.176ex;" alt="{\displaystyle {\tfrac {a}{2}}=r\tan({\tfrac {\pi }{n}})=R\sin({\tfrac {\pi }{n}})}"></span><br /> <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle r:}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>r</mi> <mo>:</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle r:}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/4e953871da035a97eb7aded88277ad1a47205893" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:2.341ex; height:1.676ex;" alt="{\displaystyle r:}"></span> <a href="/wiki/Incircle" class="mw-redirect" title="Incircle">incircle</a> radius<br /> <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle R:}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>R</mi> <mo>:</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle R:}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/470e63632cae3e604afbf95bd86a9d950ed7e4b0" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:3.056ex; height:2.176ex;" alt="{\displaystyle R:}"></span> <a href="/wiki/Circumcircle" title="Circumcircle">circumcircle</a> radius </p> </td></tr> <tr> <td><a href="/wiki/Circle" title="Circle">Circle</a> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A=\pi r^{2}={\frac {\pi d^{2}}{4}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mi>&#x03C0;<!-- π --></mi> <msup> <mi>r</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mi>&#x03C0;<!-- π --></mi> <msup> <mi>d</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> </mrow> <mn>4</mn> </mfrac> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A=\pi r^{2}={\frac {\pi d^{2}}{4}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/ac5e6bb24b18aa77e1e419ff1e09240456892a7e" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.838ex; width:15.815ex; height:5.676ex;" alt="{\displaystyle A=\pi r^{2}={\frac {\pi d^{2}}{4}}}"></span><br /> <p>(<span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle d=2r:}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>d</mi> <mo>=</mo> <mn>2</mn> <mi>r</mi> <mo>:</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle d=2r:}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/db5ab3607f5070f24d3f689368508e88e45465e5" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:7.817ex; height:2.176ex;" alt="{\displaystyle d=2r:}"></span> <a href="/wiki/Diameter" title="Diameter">diameter</a>) </p> </td> <td><span typeof="mw:File"><a href="/wiki/File:Kreis-r-tab.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b5/Kreis-r-tab.svg/100px-Kreis-r-tab.svg.png" decoding="async" width="100" height="100" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b5/Kreis-r-tab.svg/150px-Kreis-r-tab.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b5/Kreis-r-tab.svg/200px-Kreis-r-tab.svg.png 2x" data-file-width="94" data-file-height="94" /></a></span> </td></tr> <tr> <td><a href="/wiki/Circular_sector" title="Circular sector">Circular sector</a> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A={\frac {\theta }{2}}r^{2}={\frac {L\cdot r}{2}}\,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mi>&#x03B8;<!-- θ --></mi> <mn>2</mn> </mfrac> </mrow> <msup> <mi>r</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mi>L</mi> <mo>&#x22C5;<!-- ⋅ --></mo> <mi>r</mi> </mrow> <mn>2</mn> </mfrac> </mrow> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A={\frac {\theta }{2}}r^{2}={\frac {L\cdot r}{2}}\,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/9100301d343d3fbff54c4eb6579378b2a0d35e87" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.838ex; margin-right: -0.387ex; width:17.575ex; height:5.343ex;" alt="{\displaystyle A={\frac {\theta }{2}}r^{2}={\frac {L\cdot r}{2}}\,\!}"></span> </td> <td><span typeof="mw:File"><a href="/wiki/File:Circle_arc.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/d/da/Circle_arc.svg/120px-Circle_arc.svg.png" decoding="async" width="120" height="108" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/da/Circle_arc.svg/180px-Circle_arc.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/da/Circle_arc.svg/240px-Circle_arc.svg.png 2x" data-file-width="779" data-file-height="703" /></a></span> </td></tr> <tr> <td><a href="/wiki/Ellipse" title="Ellipse">Ellipse</a> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A=\pi ab\,\!}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mi>&#x03C0;<!-- π --></mi> <mi>a</mi> <mi>b</mi> <mspace width="thinmathspace" /> <mspace width="negativethinmathspace" /> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A=\pi ab\,\!}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/054e5e946a7a106ca68c7ca0f3cae845621b678f" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; margin-right: -0.387ex; width:8.788ex; height:2.176ex;" alt="{\displaystyle A=\pi ab\,\!}"></span> </td> <td><span typeof="mw:File"><a href="/wiki/File:Ellipse-ab-tab.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b9/Ellipse-ab-tab.svg/120px-Ellipse-ab-tab.svg.png" decoding="async" width="120" height="64" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b9/Ellipse-ab-tab.svg/180px-Ellipse-ab-tab.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b9/Ellipse-ab-tab.svg/240px-Ellipse-ab-tab.svg.png 2x" data-file-width="129" data-file-height="69" /></a></span> </td></tr> <tr> <td><a href="/wiki/Integral" title="Integral">Integral</a> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A=\int _{a}^{b}f(x)\mathrm {d} x,\ f(x)\geq 0}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <msubsup> <mo>&#x222B;<!-- ∫ --></mo> <mrow class="MJX-TeXAtom-ORD"> <mi>a</mi> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mi>b</mi> </mrow> </msubsup> <mi>f</mi> <mo stretchy="false">(</mo> <mi>x</mi> <mo stretchy="false">)</mo> <mrow class="MJX-TeXAtom-ORD"> <mi mathvariant="normal">d</mi> </mrow> <mi>x</mi> <mo>,</mo> <mtext>&#xA0;</mtext> <mi>f</mi> <mo stretchy="false">(</mo> <mi>x</mi> <mo stretchy="false">)</mo> <mo>&#x2265;<!-- ≥ --></mo> <mn>0</mn> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A=\int _{a}^{b}f(x)\mathrm {d} x,\ f(x)\geq 0}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/d3d989a91365109ea3815cf4d773358cb626f35c" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.338ex; width:25.963ex; height:6.343ex;" alt="{\displaystyle A=\int _{a}^{b}f(x)\mathrm {d} x,\ f(x)\geq 0}"></span> </td> <td><span class="mw-default-size" typeof="mw:File"><a href="/wiki/File:Vase-f-fx-tab.svg" class="mw-file-description" title="hochkant=0.2"><img alt="hochkant=0.2" src="//upload.wikimedia.org/wikipedia/commons/thumb/7/78/Vase-f-fx-tab.svg/218px-Vase-f-fx-tab.svg.png" decoding="async" width="218" height="82" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/78/Vase-f-fx-tab.svg/327px-Vase-f-fx-tab.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/78/Vase-f-fx-tab.svg/436px-Vase-f-fx-tab.svg.png 2x" data-file-width="218" data-file-height="82" /></a></span> </td></tr> <tr> <td> </td> <td><b><a href="/wiki/Surface_area" title="Surface area">Surface area</a></b> </td> <td> </td></tr> <tr> <td><a href="/wiki/Sphere_(geometry)" class="mw-redirect" title="Sphere (geometry)">Sphere</a><br /> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A=4\pi r^{2}=\pi d^{2}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mn>4</mn> <mi>&#x03C0;<!-- π --></mi> <msup> <mi>r</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mo>=</mo> <mi>&#x03C0;<!-- π --></mi> <msup> <mi>d</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A=4\pi r^{2}=\pi d^{2}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/825e9926272f5a3c5c4a283b2fa4de7f848f65eb" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:16.142ex; height:2.676ex;" alt="{\displaystyle A=4\pi r^{2}=\pi d^{2}}"></span> </td> <td><span typeof="mw:File"><a href="/wiki/File:Kugel-1-tab.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/b/ba/Kugel-1-tab.svg/100px-Kugel-1-tab.svg.png" decoding="async" width="100" height="100" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/ba/Kugel-1-tab.svg/150px-Kugel-1-tab.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/ba/Kugel-1-tab.svg/200px-Kugel-1-tab.svg.png 2x" data-file-width="155" data-file-height="155" /></a></span> </td></tr> <tr> <td><a href="/wiki/Cuboid" title="Cuboid">Cuboid</a> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A=2(ab+ac+bc)}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mn>2</mn> <mo stretchy="false">(</mo> <mi>a</mi> <mi>b</mi> <mo>+</mo> <mi>a</mi> <mi>c</mi> <mo>+</mo> <mi>b</mi> <mi>c</mi> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A=2(ab+ac+bc)}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/13ffa91220b550ac15eb01ab747e37965bf33f31" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:19.963ex; height:2.843ex;" alt="{\displaystyle A=2(ab+ac+bc)}"></span> </td> <td><span typeof="mw:File"><a href="/wiki/File:Quader-1-tab.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/7/7f/Quader-1-tab.svg/150px-Quader-1-tab.svg.png" decoding="async" width="150" height="85" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/7f/Quader-1-tab.svg/225px-Quader-1-tab.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/7f/Quader-1-tab.svg/300px-Quader-1-tab.svg.png 2x" data-file-width="187" data-file-height="106" /></a></span> </td></tr> <tr> <td><a href="/wiki/Cylinder_(geometry)" class="mw-redirect" title="Cylinder (geometry)">Cylinder</a><br /> <p>(incl. bottom and top) </p> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A=2\pi r(r+h)}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mn>2</mn> <mi>&#x03C0;<!-- π --></mi> <mi>r</mi> <mo stretchy="false">(</mo> <mi>r</mi> <mo>+</mo> <mi>h</mi> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A=2\pi r(r+h)}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/c58f5516eb7757a4ef57213291c912b0230f013d" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:15.422ex; height:2.843ex;" alt="{\displaystyle A=2\pi r(r+h)}"></span> </td> <td><span typeof="mw:File"><a href="/wiki/File:Zylinder-1-tab.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/8/81/Zylinder-1-tab.svg/120px-Zylinder-1-tab.svg.png" decoding="async" width="120" height="125" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/81/Zylinder-1-tab.svg/180px-Zylinder-1-tab.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/81/Zylinder-1-tab.svg/240px-Zylinder-1-tab.svg.png 2x" data-file-width="155" data-file-height="162" /></a></span> </td></tr> <tr> <td><a href="/wiki/Cone" title="Cone">Cone</a><br /> <p>(incl. bottom) </p> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A=\pi r(r+{\sqrt {r^{2}+h^{2}}})}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mi>&#x03C0;<!-- π --></mi> <mi>r</mi> <mo stretchy="false">(</mo> <mi>r</mi> <mo>+</mo> <mrow class="MJX-TeXAtom-ORD"> <msqrt> <msup> <mi>r</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mo>+</mo> <msup> <mi>h</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> </msqrt> </mrow> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A=\pi r(r+{\sqrt {r^{2}+h^{2}}})}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/4b54715931f51016de066caef9cb9711379bba25" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:22.581ex; height:3.509ex;" alt="{\displaystyle A=\pi r(r+{\sqrt {r^{2}+h^{2}}})}"></span> </td> <td><span typeof="mw:File"><a href="/wiki/File:Kegel-1-tab.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/8/8e/Kegel-1-tab.svg/120px-Kegel-1-tab.svg.png" decoding="async" width="120" height="108" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/8e/Kegel-1-tab.svg/180px-Kegel-1-tab.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/8e/Kegel-1-tab.svg/240px-Kegel-1-tab.svg.png 2x" data-file-width="153" data-file-height="138" /></a></span> </td></tr> <tr> <td><a href="/wiki/Torus" title="Torus">Torus</a> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A=4\pi ^{2}\cdot R\cdot r}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mn>4</mn> <msup> <mi>&#x03C0;<!-- π --></mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mo>&#x22C5;<!-- ⋅ --></mo> <mi>R</mi> <mo>&#x22C5;<!-- ⋅ --></mo> <mi>r</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A=4\pi ^{2}\cdot R\cdot r}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/f884b29b1cdb02a79746fe57e1107ff81a94ff37" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:14.563ex; height:2.676ex;" alt="{\displaystyle A=4\pi ^{2}\cdot R\cdot r}"></span> </td> <td><span typeof="mw:File"><a href="/wiki/File:Torus-1-tab.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/e/e8/Torus-1-tab.svg/200px-Torus-1-tab.svg.png" decoding="async" width="200" height="59" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/e8/Torus-1-tab.svg/300px-Torus-1-tab.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/e8/Torus-1-tab.svg/400px-Torus-1-tab.svg.png 2x" data-file-width="285" data-file-height="84" /></a></span> </td></tr> <tr> <td><a href="/wiki/Surface_of_revolution" title="Surface of revolution">Surface of revolution</a> </td> <td><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A=2\pi \int _{a}^{b}\!f(x){\sqrt {1+\left[f'(x)\right]^{2}}}\mathrm {d} x}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mn>2</mn> <mi>&#x03C0;<!-- π --></mi> <msubsup> <mo>&#x222B;<!-- ∫ --></mo> <mrow class="MJX-TeXAtom-ORD"> <mi>a</mi> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mi>b</mi> </mrow> </msubsup> <mspace width="negativethinmathspace" /> <mi>f</mi> <mo stretchy="false">(</mo> <mi>x</mi> <mo stretchy="false">)</mo> <mrow class="MJX-TeXAtom-ORD"> <msqrt> <mn>1</mn> <mo>+</mo> <msup> <mrow> <mo>[</mo> <mrow> <msup> <mi>f</mi> <mo>&#x2032;</mo> </msup> <mo stretchy="false">(</mo> <mi>x</mi> <mo stretchy="false">)</mo> </mrow> <mo>]</mo> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> </msqrt> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mi mathvariant="normal">d</mi> </mrow> <mi>x</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A=2\pi \int _{a}^{b}\!f(x){\sqrt {1+\left[f'(x)\right]^{2}}}\mathrm {d} x}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/07cf6da325a77c650339de80d9b00d984ca3751d" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.338ex; width:31.983ex; height:6.343ex;" alt="{\displaystyle A=2\pi \int _{a}^{b}\!f(x){\sqrt {1+\left[f&#039;(x)\right]^{2}}}\mathrm {d} x}"></span><br /> <p>(rotation around the x-axis) </p> </td> <td><span typeof="mw:File"><a href="/wiki/File:Vase-1-tab.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/e/e8/Vase-1-tab.svg/220px-Vase-1-tab.svg.png" decoding="async" width="220" height="117" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/e/e8/Vase-1-tab.svg/330px-Vase-1-tab.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/e/e8/Vase-1-tab.svg/440px-Vase-1-tab.svg.png 2x" data-file-width="396" data-file-height="210" /></a></span> </td></tr> </tbody></table> <p>The above calculations show how to find the areas of many common <a href="/wiki/Shapes" class="mw-redirect" title="Shapes">shapes</a>. </p><p>The areas of irregular (and thus arbitrary) polygons can be calculated using the "<a href="/wiki/Surveyor%27s_formula" class="mw-redirect" title="Surveyor&#39;s formula">Surveyor's formula</a>" (shoelace formula).<sup id="cite_ref-Surveyor_28-1" class="reference"><a href="#cite_note-Surveyor-28"><span class="cite-bracket">&#91;</span>28<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Relation_of_area_to_perimeter">Relation of area to perimeter</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=27" title="Edit section: Relation of area to perimeter"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <a href="/wiki/Isoperimetric_inequality" title="Isoperimetric inequality">isoperimetric inequality</a> states that, for a closed curve of length <i>L</i> (so the region it encloses has <a href="/wiki/Perimeter" title="Perimeter">perimeter</a> <i>L</i>) and for area <i>A</i> of the region that it encloses, </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle 4\pi A\leq L^{2},}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mn>4</mn> <mi>&#x03C0;<!-- π --></mi> <mi>A</mi> <mo>&#x2264;<!-- ≤ --></mo> <msup> <mi>L</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mo>,</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle 4\pi A\leq L^{2},}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/dd8bd2c0d6a1230d3672a79f0974b1488aa89df1" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:10.62ex; height:3.009ex;" alt="{\displaystyle 4\pi A\leq L^{2},}"></span></dd></dl> <p>and equality holds if and only if the curve is a <a href="/wiki/Circle" title="Circle">circle</a>. Thus a circle has the largest area of any closed figure with a given perimeter. </p><p>At the other extreme, a figure with given perimeter <i>L</i> could have an arbitrarily small area, as illustrated by a <a href="/wiki/Rhombus" title="Rhombus">rhombus</a> that is "tipped over" arbitrarily far so that two of its <a href="/wiki/Angle" title="Angle">angles</a> are arbitrarily close to 0° and the other two are arbitrarily close to 180°. </p><p>For a circle, the ratio of the area to the <a href="/wiki/Circumference" title="Circumference">circumference</a> (the term for the perimeter of a circle) equals half the <a href="/wiki/Radius" title="Radius">radius</a> <i>r</i>. This can be seen from the area formula <i>πr</i><sup>2</sup> and the circumference formula 2<i>πr</i>. </p><p>The area of a <a href="/wiki/Regular_polygon" title="Regular polygon">regular polygon</a> is half its perimeter times the <a href="/wiki/Apothem" title="Apothem">apothem</a> (where the apothem is the distance from the center to the nearest point on any side). </p> <div class="mw-heading mw-heading3"><h3 id="Fractals">Fractals</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=28" title="Edit section: Fractals"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Doubling the edge lengths of a polygon multiplies its area by four, which is two (the ratio of the new to the old side length) raised to the power of two (the dimension of the space the polygon resides in). But if the one-dimensional lengths of a <a href="/wiki/Fractal" title="Fractal">fractal</a> drawn in two dimensions are all doubled, the spatial content of the fractal scales by a power of two that is not necessarily an integer. This power is called the <a href="/wiki/Fractal_dimension" title="Fractal dimension">fractal dimension</a> of the fractal. <sup id="cite_ref-Mandelbrot1983_33-0" class="reference"><a href="#cite_note-Mandelbrot1983-33"><span class="cite-bracket">&#91;</span>33<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Area_bisectors">Area bisectors</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=29" title="Edit section: Area bisectors"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Bisection#Area_bisectors_and_perimeter_bisectors" title="Bisection">Bisection §&#160;Area bisectors and perimeter bisectors</a></div> <p>There are an infinitude of lines that bisect the area of a triangle. Three of them are the <a href="/wiki/Median_(triangle)" class="mw-redirect" title="Median (triangle)">medians</a> of the triangle (which connect the sides' midpoints with the opposite vertices), and these are <a href="/wiki/Concurrent_lines" title="Concurrent lines">concurrent</a> at the triangle's <a href="/wiki/Centroid" title="Centroid">centroid</a>; indeed, they are the only area bisectors that go through the centroid. Any line through a triangle that splits both the triangle's area and its perimeter in half goes through the triangle's incenter (the center of its <a href="/wiki/Incircle" class="mw-redirect" title="Incircle">incircle</a>). There are either one, two, or three of these for any given triangle. </p><p>Any line through the midpoint of a parallelogram bisects the area. </p><p>All area bisectors of a circle or other ellipse go through the center, and any <a href="/wiki/Chord_(geometry)" title="Chord (geometry)">chords</a> through the center bisect the area. In the case of a circle they are the diameters of the circle. </p> <div class="mw-heading mw-heading2"><h2 id="Optimization">Optimization</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=30" title="Edit section: Optimization"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Given a wire contour, the surface of least area spanning ("filling") it is a <a href="/wiki/Minimal_surface" title="Minimal surface">minimal surface</a>. Familiar examples include <a href="/wiki/Soap_bubble" title="Soap bubble">soap bubbles</a>. </p><p>The question of the <a href="/wiki/Filling_area_conjecture" title="Filling area conjecture">filling area</a> of the <a href="/wiki/Riemannian_circle" class="mw-redirect" title="Riemannian circle">Riemannian circle</a> remains open.<sup id="cite_ref-34" class="reference"><a href="#cite_note-34"><span class="cite-bracket">&#91;</span>34<span class="cite-bracket">&#93;</span></a></sup> </p><p>The circle has the largest area of any two-dimensional object having the same perimeter. </p><p>A <a href="/wiki/Cyclic_polygon" class="mw-redirect" title="Cyclic polygon">cyclic polygon</a> (one inscribed in a circle) has the largest area of any polygon with a given number of sides of the same lengths. </p><p>A version of the <a href="/wiki/Isoperimetric_inequality" title="Isoperimetric inequality">isoperimetric inequality</a> for triangles states that the triangle of greatest area among all those with a given perimeter is <a href="/wiki/Equilateral" class="mw-redirect" title="Equilateral">equilateral</a>.<sup id="cite_ref-Chakerian_35-0" class="reference"><a href="#cite_note-Chakerian-35"><span class="cite-bracket">&#91;</span>35<span class="cite-bracket">&#93;</span></a></sup> </p><p>The triangle of largest area of all those inscribed in a given circle is equilateral; and the triangle of smallest area of all those circumscribed around a given circle is equilateral.<sup id="cite_ref-36" class="reference"><a href="#cite_note-36"><span class="cite-bracket">&#91;</span>36<span class="cite-bracket">&#93;</span></a></sup> </p><p>The ratio of the area of the incircle to the area of an equilateral triangle, <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\frac {\pi }{3{\sqrt {3}}}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mi>&#x03C0;<!-- π --></mi> <mrow> <mn>3</mn> <mrow class="MJX-TeXAtom-ORD"> <msqrt> <mn>3</mn> </msqrt> </mrow> </mrow> </mfrac> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle {\frac {\pi }{3{\sqrt {3}}}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/9e87580f1fcf9c9b18a8e4a5d9261491e79b8bf8" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.838ex; width:5.097ex; height:5.676ex;" alt="{\displaystyle {\frac {\pi }{3{\sqrt {3}}}}}"></span>, is larger than that of any non-equilateral triangle.<sup id="cite_ref-37" class="reference"><a href="#cite_note-37"><span class="cite-bracket">&#91;</span>37<span class="cite-bracket">&#93;</span></a></sup> </p><p>The ratio of the area to the square of the perimeter of an equilateral triangle, <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\frac {1}{12{\sqrt {3}}}},}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mn>1</mn> <mrow> <mn>12</mn> <mrow class="MJX-TeXAtom-ORD"> <msqrt> <mn>3</mn> </msqrt> </mrow> </mrow> </mfrac> </mrow> <mo>,</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle {\frac {1}{12{\sqrt {3}}}},}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/844409c74d8d57e537c55a4c22aeea1a25ecd65a" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.838ex; width:6.906ex; height:6.176ex;" alt="{\displaystyle {\frac {1}{12{\sqrt {3}}}},}"></span> is larger than that for any other triangle.<sup id="cite_ref-Chakerian_35-1" class="reference"><a href="#cite_note-Chakerian-35"><span class="cite-bracket">&#91;</span>35<span class="cite-bracket">&#93;</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=31" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Brahmagupta_quadrilateral" class="mw-redirect" title="Brahmagupta quadrilateral">Brahmagupta quadrilateral</a>, a cyclic quadrilateral with integer sides, integer diagonals, and integer area.</li> <li><a href="/wiki/Equiareal_map" title="Equiareal map">Equiareal map</a></li> <li><a href="/wiki/Heronian_triangle" title="Heronian triangle">Heronian triangle</a>, a triangle with integer sides and integer area.</li> <li><a href="/wiki/List_of_triangle_inequalities#Area" title="List of triangle inequalities">List of triangle inequalities</a></li> <li><a href="/wiki/One-seventh_area_triangle" title="One-seventh area triangle">One-seventh area triangle</a>, an inner triangle with one-seventh the area of the reference triangle.</li></ul> <dl><dd><ul><li><a href="/wiki/Routh%27s_theorem" title="Routh&#39;s theorem">Routh's theorem</a>, a generalization of the one-seventh area triangle.</li></ul></dd></dl> <ul><li><a href="/wiki/Orders_of_magnitude_(area)" title="Orders of magnitude (area)">Orders of magnitude</a>—A list of areas by size.</li> <li><a href="/wiki/Pentagon#Derivation_of_the_area_formula" title="Pentagon">Derivation of the formula of a pentagon</a></li> <li><a href="/wiki/Planimeter" title="Planimeter">Planimeter</a>, an instrument for measuring small areas, e.g. on maps.</li> <li><a href="/wiki/Quadrilateral#Area_of_a_convex_quadrilateral" title="Quadrilateral">Area of a convex quadrilateral</a></li> <li><a href="/wiki/Robbins_pentagon" title="Robbins pentagon">Robbins pentagon</a>, a cyclic pentagon whose side lengths and area are all rational numbers.</li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=32" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-MathWorld-1"><span class="mw-cite-backlink">^ <a href="#cite_ref-MathWorld_1-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-MathWorld_1-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-MathWorld_1-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-MathWorld_1-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-MathWorld_1-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-MathWorld_1-5"><sup><i><b>f</b></i></sup></a></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFWeisstein,_Eric_W." class="citation web cs1"><a href="/wiki/Eric_W._Weisstein" title="Eric W. Weisstein">Weisstein, Eric W.</a> <a rel="nofollow" class="external text" href="http://mathworld.wolfram.com/Area.html">"Area"</a>. <a href="/wiki/Wolfram_MathWorld" class="mw-redirect" title="Wolfram MathWorld">Wolfram MathWorld</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20120505085753/http://mathworld.wolfram.com/Area.html">Archived</a> from the original on 5 May 2012<span class="reference-accessdate">. Retrieved <span class="nowrap">3 July</span> 2012</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=Area&amp;rft.pub=Wolfram+MathWorld&amp;rft.au=Weisstein%2C+Eric+W.&amp;rft_id=http%3A%2F%2Fmathworld.wolfram.com%2FArea.html&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-AF-2"><span class="mw-cite-backlink">^ <a href="#cite_ref-AF_2-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-AF_2-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-AF_2-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-AF_2-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-AF_2-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-AF_2-5"><sup><i><b>f</b></i></sup></a> <a href="#cite_ref-AF_2-6"><sup><i><b>g</b></i></sup></a> <a href="#cite_ref-AF_2-7"><sup><i><b>h</b></i></sup></a> <a href="#cite_ref-AF_2-8"><sup><i><b>i</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.math.com/tables/geometry/areas.htm">"Area Formulas"</a>. Math.com. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20120702135710/http://www.math.com/tables/geometry/areas.htm">Archived</a> from the original on 2 July 2012<span class="reference-accessdate">. Retrieved <span class="nowrap">2 July</span> 2012</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=Area+Formulas&amp;rft.pub=Math.com&amp;rft_id=http%3A%2F%2Fwww.math.com%2Ftables%2Fgeometry%2Fareas.htm&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-B-3"><span class="mw-cite-backlink">^ <a href="#cite_ref-B_3-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-B_3-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.bipm.org/en/CGPM/db/11/12/">"Resolution 12 of the 11th meeting of the CGPM (1960)"</a>. <a href="/wiki/Bureau_International_des_Poids_et_Mesures" class="mw-redirect" title="Bureau International des Poids et Mesures">Bureau International des Poids et Mesures</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20120728105135/http://www.bipm.org/en/CGPM/db/11/12/">Archived</a> from the original on 2012-07-28<span class="reference-accessdate">. Retrieved <span class="nowrap">15 July</span> 2012</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=Resolution+12+of+the+11th+meeting+of+the+CGPM+%281960%29&amp;rft.pub=Bureau+International+des+Poids+et+Mesures&amp;rft_id=http%3A%2F%2Fwww.bipm.org%2Fen%2FCGPM%2Fdb%2F11%2F12%2F&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-bkos-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-bkos_4-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMark_de_BergMarc_van_KreveldMark_OvermarsOtfried_Schwarzkopf2000" class="citation book cs1">Mark de Berg; Marc van Kreveld; <a href="/wiki/Mark_Overmars" title="Mark Overmars">Mark Overmars</a>; Otfried Schwarzkopf (2000). <a rel="nofollow" class="external text" href="https://archive.org/details/computationalgeo00berg/page/45">"Chapter 3: Polygon Triangulation"</a>. <i>Computational Geometry</i> (2nd revised&#160;ed.). <a href="/wiki/Springer-Verlag" class="mw-redirect" title="Springer-Verlag">Springer-Verlag</a>. pp.&#160;<a rel="nofollow" class="external text" href="https://archive.org/details/computationalgeo00berg/page/45">45–61</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-3-540-65620-3" title="Special:BookSources/978-3-540-65620-3"><bdi>978-3-540-65620-3</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=bookitem&amp;rft.atitle=Chapter+3%3A+Polygon+Triangulation&amp;rft.btitle=Computational+Geometry&amp;rft.pages=45-61&amp;rft.edition=2nd+revised&amp;rft.pub=Springer-Verlag&amp;rft.date=2000&amp;rft.isbn=978-3-540-65620-3&amp;rft.au=Mark+de+Berg&amp;rft.au=Marc+van+Kreveld&amp;rft.au=Mark+Overmars&amp;rft.au=Otfried+Schwarzkopf&amp;rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fcomputationalgeo00berg%2Fpage%2F45&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBoyer1959" class="citation book cs1"><a href="/wiki/Carl_Benjamin_Boyer" title="Carl Benjamin Boyer">Boyer, Carl B.</a> (1959). <a rel="nofollow" class="external text" href="https://archive.org/details/historyofcalculu00boye"><i>A History of the Calculus and Its Conceptual Development</i></a>. Dover. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-486-60509-8" title="Special:BookSources/978-0-486-60509-8"><bdi>978-0-486-60509-8</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=A+History+of+the+Calculus+and+Its+Conceptual+Development&amp;rft.pub=Dover&amp;rft.date=1959&amp;rft.isbn=978-0-486-60509-8&amp;rft.aulast=Boyer&amp;rft.aufirst=Carl+B.&amp;rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fhistoryofcalculu00boye&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-MathWorldSurfaceArea-6"><span class="mw-cite-backlink">^ <a href="#cite_ref-MathWorldSurfaceArea_6-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-MathWorldSurfaceArea_6-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-MathWorldSurfaceArea_6-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFWeisstein,_Eric_W." class="citation web cs1"><a href="/wiki/Eric_W._Weisstein" title="Eric W. Weisstein">Weisstein, Eric W.</a> <a rel="nofollow" class="external text" href="http://mathworld.wolfram.com/SurfaceArea.html">"Surface Area"</a>. <a href="/wiki/Wolfram_MathWorld" class="mw-redirect" title="Wolfram MathWorld">Wolfram MathWorld</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20120623021029/http://mathworld.wolfram.com/SurfaceArea.html">Archived</a> from the original on 23 June 2012<span class="reference-accessdate">. Retrieved <span class="nowrap">3 July</span> 2012</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=Surface+Area&amp;rft.pub=Wolfram+MathWorld&amp;rft.au=Weisstein%2C+Eric+W.&amp;rft_id=http%3A%2F%2Fmathworld.wolfram.com%2FSurfaceArea.html&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.ck12.org/c/geometry/surface-area/lesson/Surface-Area-and-Nets-GEO-CCSS/">"Surface Area"</a>. <i>CK-12 Foundation</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2018-10-09</span></span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=CK-12+Foundation&amp;rft.atitle=Surface+Area&amp;rft_id=https%3A%2F%2Fwww.ck12.org%2Fc%2Fgeometry%2Fsurface-area%2Flesson%2FSurface-Area-and-Nets-GEO-CCSS%2F&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-doCarmo-8"><span class="mw-cite-backlink">^ <a href="#cite_ref-doCarmo_8-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-doCarmo_8-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><a href="/wiki/Manfredo_do_Carmo" title="Manfredo do Carmo">do Carmo, Manfredo</a> (1976). <i>Differential Geometry of Curves and Surfaces</i>. Prentice-Hall. p. 98, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-13-212589-5" title="Special:BookSources/978-0-13-212589-5">978-0-13-212589-5</a></span> </li> <li id="cite_note-Rudin-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-Rudin_9-0">^</a></b></span> <span class="reference-text">Walter Rudin (1966). <i>Real and Complex Analysis</i>, McGraw-Hill, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/0-07-100276-6" title="Special:BookSources/0-07-100276-6">0-07-100276-6</a>.</span> </li> <li id="cite_note-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-10">^</a></b></span> <span class="reference-text">Gerald Folland (1999). <i>Real Analysis: modern techniques and their applications</i>, John Wiley &amp; Sons, Inc., p. 20, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/0-471-31716-0" title="Special:BookSources/0-471-31716-0">0-471-31716-0</a></span> </li> <li id="cite_note-Apostol-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-Apostol_11-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFApostol1967" class="citation book cs1 cs1-prop-long-vol">Apostol, Tom (1967). <i>Calculus</i>. Vol.&#160;I: One-Variable Calculus, with an Introduction to Linear Algebra. pp.&#160;58–59. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/9780471000051" title="Special:BookSources/9780471000051"><bdi>9780471000051</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Calculus&amp;rft.pages=58-59&amp;rft.date=1967&amp;rft.isbn=9780471000051&amp;rft.aulast=Apostol&amp;rft.aufirst=Tom&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-Moise-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-Moise_12-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMoise1963" class="citation book cs1">Moise, Edwin (1963). <span class="id-lock-registration" title="Free registration required"><a rel="nofollow" class="external text" href="https://archive.org/details/elementarygeomet0000mois"><i>Elementary Geometry from an Advanced Standpoint</i></a></span>. Addison-Wesley Pub. Co<span class="reference-accessdate">. Retrieved <span class="nowrap">15 July</span> 2012</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Elementary+Geometry+from+an+Advanced+Standpoint&amp;rft.pub=Addison-Wesley+Pub.+Co.&amp;rft.date=1963&amp;rft.aulast=Moise&amp;rft.aufirst=Edwin&amp;rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Felementarygeomet0000mois&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-BIPM2006Ch5-13"><span class="mw-cite-backlink">^ <a href="#cite_ref-BIPM2006Ch5_13-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-BIPM2006Ch5_13-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-BIPM2006Ch5_13-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-BIPM2006Ch5_13-3"><sup><i><b>d</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBureau_international_des_poids_et_mesures2006" class="citation cs1">Bureau international des poids et mesures (2006). <a rel="nofollow" class="external text" href="http://www.bipm.org/utils/common/pdf/si_brochure_8_en.pdf"><i>The International System of Units (SI)</i></a> <span class="cs1-format">(PDF)</span>. 8th ed. Chapter 5. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20131105051930/http://www.bipm.org/utils/common/pdf/si_brochure_8_en.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 2013-11-05<span class="reference-accessdate">. Retrieved <span class="nowrap">2008-02-13</span></span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=The+International+System+of+Units+%28SI%29&amp;rft.series=8th+ed.&amp;rft.pages=Chapter+5&amp;rft.date=2006&amp;rft.au=Bureau+international+des+poids+et+mesures&amp;rft_id=http%3A%2F%2Fwww.bipm.org%2Futils%2Fcommon%2Fpdf%2Fsi_brochure_8_en.pdf&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-14">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.magicbricks.com/blog/land-measurements-units-india/115035.html">"Land Measurement Units in India: Standard Measurement Units, Land Conversion Table"</a>. <i>Magicbricks Blog</i>. 2020-08-04<span class="reference-accessdate">. Retrieved <span class="nowrap">2023-09-20</span></span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=Magicbricks+Blog&amp;rft.atitle=Land+Measurement+Units+in+India%3A+Standard+Measurement+Units%2C+Land+Conversion+Table&amp;rft.date=2020-08-04&amp;rft_id=https%3A%2F%2Fwww.magicbricks.com%2Fblog%2Fland-measurements-units-india%2F115035.html&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-15"><span class="mw-cite-backlink"><b><a href="#cite_ref-15">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMishra2023" class="citation web cs1">Mishra, Sunita (2023-06-13). <a rel="nofollow" class="external text" href="https://housing.com/news/local-land-measurement-units-in-india/">"Land is measured in what units in India: All Types In 2023"</a>. <i>Housing News</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2023-09-20</span></span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=Housing+News&amp;rft.atitle=Land+is+measured+in+what+units+in+India%3A+All+Types+In+2023&amp;rft.date=2023-06-13&amp;rft.aulast=Mishra&amp;rft.aufirst=Sunita&amp;rft_id=https%3A%2F%2Fhousing.com%2Fnews%2Flocal-land-measurement-units-in-india%2F&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-16"><span class="mw-cite-backlink"><b><a href="#cite_ref-16">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://timesproperty.com/news/post/standard-land-measurement-units-in-india-blid1681">"Standard Land Measurement Units in India - Times Property"</a>. <i>timesproperty.com</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2023-09-20</span></span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=timesproperty.com&amp;rft.atitle=Standard+Land+Measurement+Units+in+India+-+Times+Property&amp;rft_id=https%3A%2F%2Ftimesproperty.com%2Fnews%2Fpost%2Fstandard-land-measurement-units-in-india-blid1681&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-17"><span class="mw-cite-backlink"><b><a href="#cite_ref-17">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFwww.clicbrics.com" class="citation web cs1">www.clicbrics.com. <a rel="nofollow" class="external text" href="https://www.clicbrics.com/blog/land-measurement-units">"9 Land Measurement Units in India You Must Know - 2022"</a>. <i>www.clicbrics.com</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2023-09-20</span></span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=www.clicbrics.com&amp;rft.atitle=9+Land+Measurement+Units+in+India+You+Must+Know+-+2022&amp;rft.au=www.clicbrics.com&amp;rft_id=https%3A%2F%2Fwww.clicbrics.com%2Fblog%2Fland-measurement-units&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-heath-18"><span class="mw-cite-backlink"><b><a href="#cite_ref-heath_18-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHeath2003" class="citation cs1"><a href="/wiki/Thomas_Little_Heath" class="mw-redirect" title="Thomas Little Heath">Heath, Thomas L.</a> (2003). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=_HZNr_mGFzQC&amp;pg=PA121"><i>A Manual of Greek Mathematics</i></a>. Courier Dover Publications. pp.&#160;121–132. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-486-43231-1" title="Special:BookSources/978-0-486-43231-1"><bdi>978-0-486-43231-1</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20160501215852/https://books.google.com/books?id=_HZNr_mGFzQC&amp;pg=PA121">Archived</a> from the original on 2016-05-01.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=A+Manual+of+Greek+Mathematics&amp;rft.pages=121-132&amp;rft.pub=Courier+Dover+Publications&amp;rft.date=2003&amp;rft.isbn=978-0-486-43231-1&amp;rft.aulast=Heath&amp;rft.aufirst=Thomas+L.&amp;rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3D_HZNr_mGFzQC%26pg%3DPA121&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-19"><span class="mw-cite-backlink"><b><a href="#cite_ref-19">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFStewart2003" class="citation book cs1">Stewart, James (2003). <a rel="nofollow" class="external text" href="https://archive.org/details/singlevariableca00stew/page/3"><i>Single variable calculus early transcendentals</i></a> (5th.&#160;ed.). Toronto ON: Brook/Cole. p.&#160;<a rel="nofollow" class="external text" href="https://archive.org/details/singlevariableca00stew/page/3">3</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-534-39330-4" title="Special:BookSources/978-0-534-39330-4"><bdi>978-0-534-39330-4</bdi></a>. <q>However, by indirect reasoning, Eudoxus (fifth century B.C.) used exhaustion to prove the familiar formula for the area of a circle: <span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle A=\pi r^{2}.}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>A</mi> <mo>=</mo> <mi>&#x03C0;<!-- π --></mi> <msup> <mi>r</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msup> <mo>.</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle A=\pi r^{2}.}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/ecdb193f0c084cce66161e383a7e8acb1eea80f1" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:8.923ex; height:2.676ex;" alt="{\displaystyle A=\pi r^{2}.}"></span></q></cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Single+variable+calculus+early+transcendentals.&amp;rft.place=Toronto+ON&amp;rft.pages=3&amp;rft.edition=5th.&amp;rft.pub=Brook%2FCole&amp;rft.date=2003&amp;rft.isbn=978-0-534-39330-4&amp;rft.aulast=Stewart&amp;rft.aufirst=James&amp;rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fsinglevariableca00stew%2Fpage%2F3&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span> </span> </li> <li id="cite_note-20"><span class="mw-cite-backlink"><b><a href="#cite_ref-20">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHeath,_Thomas_L.1921" class="citation book cs1">Heath, Thomas L. (1921). <i>A History of Greek Mathematics (Vol II)</i>. Oxford University Press. pp.&#160;321–323.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=A+History+of+Greek+Mathematics+%28Vol+II%29&amp;rft.pages=321-323&amp;rft.pub=Oxford+University+Press&amp;rft.date=1921&amp;rft.au=Heath%2C+Thomas+L.&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-21"><span class="mw-cite-backlink"><b><a href="#cite_ref-21">^</a></b></span> <span class="reference-text"><span class="citation mathworld" id="Reference-Mathworld-Heron&#39;s_Formula"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFWeisstein" class="citation web cs1"><a href="/wiki/Eric_W._Weisstein" title="Eric W. Weisstein">Weisstein, Eric W.</a> <a rel="nofollow" class="external text" href="https://mathworld.wolfram.com/HeronsFormula.html">"Heron's Formula"</a>. <i><a href="/wiki/MathWorld" title="MathWorld">MathWorld</a></i>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=MathWorld&amp;rft.atitle=Heron%27s+Formula&amp;rft.au=Weisstein%2C+Eric+W.&amp;rft_id=https%3A%2F%2Fmathworld.wolfram.com%2FHeronsFormula.html&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span></span> </li> <li id="cite_note-22"><span class="mw-cite-backlink"><b><a href="#cite_ref-22">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://central.edu/writing-anthology/2019/01/31/159/">"Euclid's Proof of the Pythagorean Theorem | Synaptic"</a>. <i>Central College</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2023-07-12</span></span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=unknown&amp;rft.jtitle=Central+College&amp;rft.atitle=Euclid%E2%80%99s+Proof+of+the+Pythagorean+Theorem+%7C+Synaptic&amp;rft_id=https%3A%2F%2Fcentral.edu%2Fwriting-anthology%2F2019%2F01%2F31%2F159%2F&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-23"><span class="mw-cite-backlink"><b><a href="#cite_ref-23">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFClark1930" class="citation book cs1">Clark, Walter Eugene (1930). <a rel="nofollow" class="external text" href="https://libarch.nmu.org.ua/bitstream/handle/GenofondUA/26818/f14e7857ef0bdd30ca0fd4ec057fe3c3.pdf"><i>The Aryabhatiya of Aryabhata: An Ancient Indian Work on Mathematics and Astronomy</i></a> <span class="cs1-format">(PDF)</span>. University of Chicago Press. p.&#160;26.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=The+Aryabhatiya+of+Aryabhata%3A+An+Ancient+Indian+Work+on+Mathematics+and+Astronomy&amp;rft.pages=26&amp;rft.pub=University+of+Chicago+Press&amp;rft.date=1930&amp;rft.aulast=Clark&amp;rft.aufirst=Walter+Eugene&amp;rft_id=https%3A%2F%2Flibarch.nmu.org.ua%2Fbitstream%2Fhandle%2FGenofondUA%2F26818%2Ff14e7857ef0bdd30ca0fd4ec057fe3c3.pdf&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-24"><span class="mw-cite-backlink"><b><a href="#cite_ref-24">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFXuYu2013" class="citation journal cs1">Xu, Wenwen; Yu, Ning (May 2013). <a rel="nofollow" class="external text" href="http://www.ams.org/journals/notices/201305/rnoti-p596.pdf">"Bridge Named After the Mathematician Who Discovered the Chinese Remainder Theorem"</a> <span class="cs1-format">(PDF)</span>. <i>Notices of the American Mathematical Society</i>. <b>60</b> (5): 596–597.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=article&amp;rft.jtitle=Notices+of+the+American+Mathematical+Society&amp;rft.atitle=Bridge+Named+After+the+Mathematician+Who+Discovered+the+Chinese+Remainder+Theorem&amp;rft.volume=60&amp;rft.issue=5&amp;rft.pages=596-597&amp;rft.date=2013-05&amp;rft.aulast=Xu&amp;rft.aufirst=Wenwen&amp;rft.au=Yu%2C+Ning&amp;rft_id=http%3A%2F%2Fwww.ams.org%2Fjournals%2Fnotices%2F201305%2Frnoti-p596.pdf&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-25"><span class="mw-cite-backlink"><b><a href="#cite_ref-25">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBourke1988" class="citation web cs1">Bourke, Paul (July 1988). <a rel="nofollow" class="external text" href="http://www.seas.upenn.edu/~sys502/extra_materials/Polygon%20Area%20and%20Centroid.pdf">"Calculating The Area And Centroid Of A Polygon"</a> <span class="cs1-format">(PDF)</span>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20120916104133/http://www.seas.upenn.edu/~sys502/extra_materials/Polygon%20Area%20and%20Centroid.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 2012-09-16<span class="reference-accessdate">. Retrieved <span class="nowrap">6 Feb</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=Calculating+The+Area+And+Centroid+Of+A+Polygon&amp;rft.date=1988-07&amp;rft.aulast=Bourke&amp;rft.aufirst=Paul&amp;rft_id=http%3A%2F%2Fwww.seas.upenn.edu%2F~sys502%2Fextra_materials%2FPolygon%2520Area%2520and%2520Centroid.pdf&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-26"><span class="mw-cite-backlink"><b><a href="#cite_ref-26">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFAverbachChein2012" class="citation cs1"><a href="/wiki/Bonnie_Averbach" title="Bonnie Averbach">Averbach, Bonnie</a>; Chein, Orin (2012). <a href="/wiki/Problem_Solving_Through_Recreational_Mathematics" title="Problem Solving Through Recreational Mathematics"><i>Problem Solving Through Recreational Mathematics</i></a>. Dover. p.&#160;<a rel="nofollow" class="external text" href="https://books.google.com/books?id=Dz_CAgAAQBAJ&amp;pg=PA306">306</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-486-13174-0" title="Special:BookSources/978-0-486-13174-0"><bdi>978-0-486-13174-0</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Problem+Solving+Through+Recreational+Mathematics&amp;rft.pages=306&amp;rft.pub=Dover&amp;rft.date=2012&amp;rft.isbn=978-0-486-13174-0&amp;rft.aulast=Averbach&amp;rft.aufirst=Bonnie&amp;rft.au=Chein%2C+Orin&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-27"><span class="mw-cite-backlink"><b><a href="#cite_ref-27">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFJoshi2002" class="citation cs1">Joshi, K. D. (2002). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=5SDcLHkelq4C&amp;pg=PA43"><i>Calculus for Scientists and Engineers: An Analytical Approach</i></a>. CRC Press. p.&#160;43. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-8493-1319-6" title="Special:BookSources/978-0-8493-1319-6"><bdi>978-0-8493-1319-6</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20160505011253/https://books.google.com/books?id=5SDcLHkelq4C&amp;pg=PA43">Archived</a> from the original on 2016-05-05.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Calculus+for+Scientists+and+Engineers%3A+An+Analytical+Approach&amp;rft.pages=43&amp;rft.pub=CRC+Press&amp;rft.date=2002&amp;rft.isbn=978-0-8493-1319-6&amp;rft.aulast=Joshi&amp;rft.aufirst=K.+D.&amp;rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3D5SDcLHkelq4C%26pg%3DPA43&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-Surveyor-28"><span class="mw-cite-backlink">^ <a href="#cite_ref-Surveyor_28-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Surveyor_28-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBraden1986" class="citation journal cs1">Braden, Bart (September 1986). <a rel="nofollow" class="external text" href="http://www.maa.org/pubs/Calc_articles/ma063.pdf">"The Surveyor's Area Formula"</a> <span class="cs1-format">(PDF)</span>. <i>The College Mathematics Journal</i>. <b>17</b> (4): 326–337. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.2307%2F2686282">10.2307/2686282</a>. <a href="/wiki/JSTOR_(identifier)" class="mw-redirect" title="JSTOR (identifier)">JSTOR</a>&#160;<a rel="nofollow" class="external text" href="https://www.jstor.org/stable/2686282">2686282</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20120627180152/http://www.maa.org/pubs/Calc_articles/ma063.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 27 June 2012<span class="reference-accessdate">. Retrieved <span class="nowrap">15 July</span> 2012</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=article&amp;rft.jtitle=The+College+Mathematics+Journal&amp;rft.atitle=The+Surveyor%27s+Area+Formula&amp;rft.volume=17&amp;rft.issue=4&amp;rft.pages=326-337&amp;rft.date=1986-09&amp;rft_id=info%3Adoi%2F10.2307%2F2686282&amp;rft_id=https%3A%2F%2Fwww.jstor.org%2Fstable%2F2686282%23id-name%3DJSTOR&amp;rft.aulast=Braden&amp;rft.aufirst=Bart&amp;rft_id=http%3A%2F%2Fwww.maa.org%2Fpubs%2FCalc_articles%2Fma063.pdf&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-Pick-29"><span class="mw-cite-backlink"><b><a href="#cite_ref-Pick_29-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFTrainin2007" class="citation journal cs1">Trainin, J. (November 2007). "An elementary proof of Pick's theorem". <i><a href="/wiki/Mathematical_Gazette" class="mw-redirect" title="Mathematical Gazette">Mathematical Gazette</a></i>. <b>91</b> (522): 536–540. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1017%2FS0025557200182270">10.1017/S0025557200182270</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a>&#160;<a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:124831432">124831432</a>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=article&amp;rft.jtitle=Mathematical+Gazette&amp;rft.atitle=An+elementary+proof+of+Pick%27s+theorem&amp;rft.volume=91&amp;rft.issue=522&amp;rft.pages=536-540&amp;rft.date=2007-11&amp;rft_id=info%3Adoi%2F10.1017%2FS0025557200182270&amp;rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A124831432%23id-name%3DS2CID&amp;rft.aulast=Trainin&amp;rft.aufirst=J.&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-30"><span class="mw-cite-backlink"><b><a href="#cite_ref-30">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation book cs1"><a rel="nofollow" class="external text" href="https://books.google.com/books?id=NFkVfrZBqpUC&amp;pg=PA51"><i>Matematika</i></a>. PT Grafindo Media Pratama. pp.&#160;51–. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-979-758-477-1" title="Special:BookSources/978-979-758-477-1"><bdi>978-979-758-477-1</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20170320100900/https://books.google.com/books?id=NFkVfrZBqpUC&amp;pg=PA51">Archived</a> from the original on 2017-03-20.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Matematika&amp;rft.pages=51-&amp;rft.pub=PT+Grafindo+Media+Pratama&amp;rft.isbn=978-979-758-477-1&amp;rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DNFkVfrZBqpUC%26pg%3DPA51&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-31"><span class="mw-cite-backlink"><b><a href="#cite_ref-31">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation book cs1"><a rel="nofollow" class="external text" href="https://books.google.com/books?id=uwqvITs8OaUC&amp;pg=PA157"><i>Get Success UN +SPMB Matematika</i></a>. PT Grafindo Media Pratama. pp.&#160;157–. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-602-00-0090-9" title="Special:BookSources/978-602-00-0090-9"><bdi>978-602-00-0090-9</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20161223115304/https://books.google.com/books?id=uwqvITs8OaUC&amp;pg=PA157">Archived</a> from the original on 2016-12-23.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=Get+Success+UN+%2BSPMB+Matematika&amp;rft.pages=157-&amp;rft.pub=PT+Grafindo+Media+Pratama&amp;rft.isbn=978-602-00-0090-9&amp;rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DuwqvITs8OaUC%26pg%3DPA157&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-MathWorldCone-32"><span class="mw-cite-backlink">^ <a href="#cite_ref-MathWorldCone_32-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-MathWorldCone_32-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-MathWorldCone_32-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFWeisstein,_Eric_W." class="citation web cs1"><a href="/wiki/Eric_W._Weisstein" title="Eric W. Weisstein">Weisstein, Eric W.</a> <a rel="nofollow" class="external text" href="http://mathworld.wolfram.com/Cone.html">"Cone"</a>. <a href="/wiki/Wolfram_MathWorld" class="mw-redirect" title="Wolfram MathWorld">Wolfram MathWorld</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20120621230050/http://mathworld.wolfram.com/Cone.html">Archived</a> from the original on 21 June 2012<span class="reference-accessdate">. Retrieved <span class="nowrap">6 July</span> 2012</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=unknown&amp;rft.btitle=Cone&amp;rft.pub=Wolfram+MathWorld&amp;rft.au=Weisstein%2C+Eric+W.&amp;rft_id=http%3A%2F%2Fmathworld.wolfram.com%2FCone.html&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-Mandelbrot1983-33"><span class="mw-cite-backlink"><b><a href="#cite_ref-Mandelbrot1983_33-0">^</a></b></span> <span class="reference-text"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMandelbrot1983" class="citation book cs1">Mandelbrot, Benoît B. (1983). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=JFX9mQEACAAJ"><i>The fractal geometry of nature</i></a>. Macmillan. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a>&#160;<a href="/wiki/Special:BookSources/978-0-7167-1186-5" title="Special:BookSources/978-0-7167-1186-5"><bdi>978-0-7167-1186-5</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20170320115652/https://books.google.com/books?id=JFX9mQEACAAJ">Archived</a> from the original on 20 March 2017<span class="reference-accessdate">. Retrieved <span class="nowrap">1 February</span> 2012</span>.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&amp;rft.genre=book&amp;rft.btitle=The+fractal+geometry+of+nature&amp;rft.pub=Macmillan&amp;rft.date=1983&amp;rft.isbn=978-0-7167-1186-5&amp;rft.aulast=Mandelbrot&amp;rft.aufirst=Beno%C3%AEt+B.&amp;rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DJFX9mQEACAAJ&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-34"><span class="mw-cite-backlink"><b><a href="#cite_ref-34">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFGromov1983" class="citation cs1">Gromov, Mikhael (1983). <a rel="nofollow" class="external text" href="http://projecteuclid.org/euclid.jdg/1214509283">"Filling Riemannian manifolds"</a>. <i>Journal of Differential Geometry</i>. <b>18</b> (1): 1–147. <a href="/wiki/CiteSeerX_(identifier)" class="mw-redirect" title="CiteSeerX (identifier)">CiteSeerX</a>&#160;<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.400.9154">10.1.1.400.9154</a></span>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.4310%2Fjdg%2F1214509283">10.4310/jdg/1214509283</a>. <a href="/wiki/MR_(identifier)" class="mw-redirect" title="MR (identifier)">MR</a>&#160;<a rel="nofollow" class="external text" href="https://mathscinet.ams.org/mathscinet-getitem?mr=0697984">0697984</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20140408110006/http://projecteuclid.org/euclid.jdg/1214509283">Archived</a> from the original on 2014-04-08.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=article&amp;rft.jtitle=Journal+of+Differential+Geometry&amp;rft.atitle=Filling+Riemannian+manifolds&amp;rft.volume=18&amp;rft.issue=1&amp;rft.pages=1-147&amp;rft.date=1983&amp;rft_id=https%3A%2F%2Fciteseerx.ist.psu.edu%2Fviewdoc%2Fsummary%3Fdoi%3D10.1.1.400.9154%23id-name%3DCiteSeerX&amp;rft_id=https%3A%2F%2Fmathscinet.ams.org%2Fmathscinet-getitem%3Fmr%3D697984%23id-name%3DMR&amp;rft_id=info%3Adoi%2F10.4310%2Fjdg%2F1214509283&amp;rft.aulast=Gromov&amp;rft.aufirst=Mikhael&amp;rft_id=http%3A%2F%2Fprojecteuclid.org%2Feuclid.jdg%2F1214509283&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> <li id="cite_note-Chakerian-35"><span class="mw-cite-backlink">^ <a href="#cite_ref-Chakerian_35-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Chakerian_35-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text">Chakerian, G.D. (1979) "A Distorted View of Geometry." Ch. 7 in <i>Mathematical Plums</i>. R. Honsberger (ed.). Washington, DC: Mathematical Association of America, p. 147.</span> </li> <li id="cite_note-36"><span class="mw-cite-backlink"><b><a href="#cite_ref-36">^</a></b></span> <span class="reference-text">Dorrie, Heinrich (1965), <i>100 Great Problems of Elementary Mathematics</i>, Dover Publ., pp. 379–380.</span> </li> <li id="cite_note-37"><span class="mw-cite-backlink"><b><a href="#cite_ref-37">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMinda,_D.Phelps,_S.2008" class="citation journal cs1">Minda, D.; Phelps, S. (October 2008). <a rel="nofollow" class="external text" href="https://www.researchgate.net/publication/228698127">"Triangles, ellipses, and cubic polynomials"</a>. <i><a href="/wiki/American_Mathematical_Monthly" class="mw-redirect" title="American Mathematical Monthly">American Mathematical Monthly</a></i>. <b>115</b> (8): 679–689: Theorem 4.1. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1080%2F00029890.2008.11920581">10.1080/00029890.2008.11920581</a>. <a href="/wiki/JSTOR_(identifier)" class="mw-redirect" title="JSTOR (identifier)">JSTOR</a>&#160;<a rel="nofollow" class="external text" href="https://www.jstor.org/stable/27642581">27642581</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a>&#160;<a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:15049234">15049234</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20161104141707/https://www.researchgate.net/publication/228698127_Triangles_ellipses_and_cubic_polynomials">Archived</a> from the original on 2016-11-04.</cite><span title="ctx_ver=Z39.88-2004&amp;rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&amp;rft.genre=article&amp;rft.jtitle=American+Mathematical+Monthly&amp;rft.atitle=Triangles%2C+ellipses%2C+and+cubic+polynomials&amp;rft.volume=115&amp;rft.issue=8&amp;rft.pages=679-689%3A+Theorem+4.1&amp;rft.date=2008-10&amp;rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A15049234%23id-name%3DS2CID&amp;rft_id=https%3A%2F%2Fwww.jstor.org%2Fstable%2F27642581%23id-name%3DJSTOR&amp;rft_id=info%3Adoi%2F10.1080%2F00029890.2008.11920581&amp;rft.au=Minda%2C+D.&amp;rft.au=Phelps%2C+S.&amp;rft_id=https%3A%2F%2Fwww.researchgate.net%2Fpublication%2F228698127&amp;rfr_id=info%3Asid%2Fen.wikipedia.org%3AArea" class="Z3988"></span></span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Area&amp;action=edit&amp;section=33" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1235681985">.mw-parser-output .side-box{margin:4px 0;box-sizing:border-box;border:1px solid #aaa;font-size:88%;line-height:1.25em;background-color:var(--background-color-interactive-subtle,#f8f9fa);display:flow-root}.mw-parser-output .side-box-abovebelow,.mw-parser-output .side-box-text{padding:0.25em 0.9em}.mw-parser-output .side-box-image{padding:2px 0 2px 0.9em;text-align:center}.mw-parser-output .side-box-imageright{padding:2px 0.9em 2px 0;text-align:center}@media(min-width:500px){.mw-parser-output .side-box-flex{display:flex;align-items:center}.mw-parser-output .side-box-text{flex:1;min-width:0}}@media(min-width:720px){.mw-parser-output .side-box{width:238px}.mw-parser-output .side-box-right{clear:right;float:right;margin-left:1em}.mw-parser-output .side-box-left{margin-right:1em}}</style><style data-mw-deduplicate="TemplateStyles:r1250146164">.mw-parser-output .sister-box .side-box-abovebelow{padding:0.75em 0;text-align:center}.mw-parser-output .sister-box .side-box-abovebelow>b{display:block}.mw-parser-output .sister-box .side-box-text>ul{border-top:1px solid #aaa;padding:0.75em 0;width:217px;margin:0 auto}.mw-parser-output .sister-box .side-box-text>ul>li{min-height:31px}.mw-parser-output .sister-logo{display:inline-block;width:31px;line-height:31px;vertical-align:middle;text-align:center}.mw-parser-output .sister-link{display:inline-block;margin-left:4px;width:182px;vertical-align:middle}@media print{body.ns-0 .mw-parser-output .sistersitebox{display:none!important}}@media screen{html.skin-theme-clientpref-night .mw-parser-output .sistersitebox img[src*="Wiktionary-logo-v2.svg"]{background-color:white}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .sistersitebox img[src*="Wiktionary-logo-v2.svg"]{background-color:white}}</style><div role="navigation" aria-labelledby="sister-projects" class="side-box metadata side-box-right sister-box sistersitebox plainlinks"><style data-mw-deduplicate="TemplateStyles:r1126788409">.mw-parser-output .plainlist ol,.mw-parser-output .plainlist ul{line-height:inherit;list-style:none;margin:0;padding:0}.mw-parser-output .plainlist ol li,.mw-parser-output .plainlist ul li{margin-bottom:0}</style> <div class="side-box-abovebelow"> <b>Area</b> at Wikipedia's <a href="/wiki/Wikipedia:Wikimedia_sister_projects" title="Wikipedia:Wikimedia sister projects"><span id="sister-projects">sister projects</span></a></div> <div class="side-box-flex"> <div class="side-box-text plainlist"><ul><li><span class="sister-logo"><span class="mw-valign-middle" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/0/06/Wiktionary-logo-v2.svg/27px-Wiktionary-logo-v2.svg.png" decoding="async" width="27" height="27" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/0/06/Wiktionary-logo-v2.svg/41px-Wiktionary-logo-v2.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/0/06/Wiktionary-logo-v2.svg/54px-Wiktionary-logo-v2.svg.png 2x" data-file-width="391" data-file-height="391" /></span></span></span><span class="sister-link"><a href="https://en.wiktionary.org/wiki/Special:Search/Area" class="extiw" title="wikt:Special:Search/Area">Definitions</a> from Wiktionary</span></li><li><span class="sister-logo"><span class="mw-valign-middle" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/20px-Commons-logo.svg.png" decoding="async" width="20" height="27" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/30px-Commons-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/40px-Commons-logo.svg.png 2x" data-file-width="1024" data-file-height="1376" /></span></span></span><span class="sister-link"><a href="https://commons.wikimedia.org/wiki/Category:Area" class="extiw" title="c:Category:Area">Media</a> from Commons</span></li><li><span class="sister-logo"><span class="mw-valign-middle" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/f/ff/Wikidata-logo.svg/27px-Wikidata-logo.svg.png" decoding="async" width="27" height="15" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/ff/Wikidata-logo.svg/41px-Wikidata-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/ff/Wikidata-logo.svg/54px-Wikidata-logo.svg.png 2x" data-file-width="1050" data-file-height="590" /></span></span></span><span class="sister-link"><a href="https://www.wikidata.org/wiki/Q11500" class="extiw" title="d:Q11500">Data</a> from Wikidata</span></li></ul></div></div> </div> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist ul dl,.mw-parser-output .hlist ul ol,.mw-parser-output .hlist ul ul{display:inline}.mw-parser-output .hlist .mw-empty-li{display:none}.mw-parser-output .hlist dt::after{content:": "}.mw-parser-output .hlist dd::after,.mw-parser-output .hlist li::after{content:" · ";font-weight:bold}.mw-parser-output .hlist dd:last-child::after,.mw-parser-output .hlist dt:last-child::after,.mw-parser-output .hlist li:last-child::after{content:none}.mw-parser-output .hlist dd dd:first-child::before,.mw-parser-output .hlist dd dt:first-child::before,.mw-parser-output .hlist dd li:first-child::before,.mw-parser-output .hlist dt dd:first-child::before,.mw-parser-output .hlist dt dt:first-child::before,.mw-parser-output .hlist dt li:first-child::before,.mw-parser-output .hlist li dd:first-child::before,.mw-parser-output .hlist li dt:first-child::before,.mw-parser-output .hlist li li:first-child::before{content:" (";font-weight:normal}.mw-parser-output .hlist dd dd:last-child::after,.mw-parser-output .hlist dd dt:last-child::after,.mw-parser-output .hlist dd li:last-child::after,.mw-parser-output .hlist dt dd:last-child::after,.mw-parser-output .hlist dt dt:last-child::after,.mw-parser-output .hlist dt li:last-child::after,.mw-parser-output .hlist li dd:last-child::after,.mw-parser-output .hlist li dt:last-child::after,.mw-parser-output .hlist li li:last-child::after{content:")";font-weight:normal}.mw-parser-output .hlist ol{counter-reset:listitem}.mw-parser-output .hlist ol>li{counter-increment:listitem}.mw-parser-output .hlist ol>li::before{content:" "counter(listitem)"\a0 "}.mw-parser-output .hlist dd ol>li:first-child::before,.mw-parser-output .hlist dt ol>li:first-child::before,.mw-parser-output .hlist li ol>li:first-child::before{content:" ("counter(listitem)"\a0 "}</style><style data-mw-deduplicate="TemplateStyles:r1236075235">.mw-parser-output .navbox{box-sizing:border-box;border:1px solid #a2a9b1;width:100%;clear:both;font-size:88%;text-align:center;padding:1px;margin:1em auto 0}.mw-parser-output .navbox .navbox{margin-top:0}.mw-parser-output .navbox+.navbox,.mw-parser-output .navbox+.navbox-styles+.navbox{margin-top:-1px}.mw-parser-output .navbox-inner,.mw-parser-output .navbox-subgroup{width:100%}.mw-parser-output .navbox-group,.mw-parser-output .navbox-title,.mw-parser-output .navbox-abovebelow{padding:0.25em 1em;line-height:1.5em;text-align:center}.mw-parser-output .navbox-group{white-space:nowrap;text-align:right}.mw-parser-output .navbox,.mw-parser-output .navbox-subgroup{background-color:#fdfdfd}.mw-parser-output .navbox-list{line-height:1.5em;border-color:#fdfdfd}.mw-parser-output .navbox-list-with-group{text-align:left;border-left-width:2px;border-left-style:solid}.mw-parser-output tr+tr>.navbox-abovebelow,.mw-parser-output tr+tr>.navbox-group,.mw-parser-output tr+tr>.navbox-image,.mw-parser-output tr+tr>.navbox-list{border-top:2px solid #fdfdfd}.mw-parser-output .navbox-title{background-color:#ccf}.mw-parser-output .navbox-abovebelow,.mw-parser-output .navbox-group,.mw-parser-output .navbox-subgroup .navbox-title{background-color:#ddf}.mw-parser-output .navbox-subgroup .navbox-group,.mw-parser-output .navbox-subgroup .navbox-abovebelow{background-color:#e6e6ff}.mw-parser-output .navbox-even{background-color:#f7f7f7}.mw-parser-output .navbox-odd{background-color:transparent}.mw-parser-output .navbox .hlist td dl,.mw-parser-output .navbox .hlist td ol,.mw-parser-output .navbox .hlist td ul,.mw-parser-output .navbox td.hlist dl,.mw-parser-output .navbox td.hlist ol,.mw-parser-output .navbox td.hlist ul{padding:0.125em 0}.mw-parser-output .navbox .navbar{display:block;font-size:100%}.mw-parser-output .navbox-title .navbar{float:left;text-align:left;margin-right:0.5em}body.skin--responsive .mw-parser-output .navbox-image img{max-width:none!important}@media print{body.ns-0 .mw-parser-output .navbox{display:none!important}}</style></div><div role="navigation" class="navbox" aria-labelledby="Classical_mechanics_SI_units" style="padding:3px"><table class="nowraplinks mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><style data-mw-deduplicate="TemplateStyles:r1239400231">.mw-parser-output .navbar{display:inline;font-size:88%;font-weight:normal}.mw-parser-output .navbar-collapse{float:left;text-align:left}.mw-parser-output .navbar-boxtext{word-spacing:0}.mw-parser-output .navbar ul{display:inline-block;white-space:nowrap;line-height:inherit}.mw-parser-output .navbar-brackets::before{margin-right:-0.125em;content:"[ "}.mw-parser-output .navbar-brackets::after{margin-left:-0.125em;content:" ]"}.mw-parser-output .navbar li{word-spacing:-0.125em}.mw-parser-output .navbar a>span,.mw-parser-output .navbar a>abbr{text-decoration:inherit}.mw-parser-output .navbar-mini abbr{font-variant:small-caps;border-bottom:none;text-decoration:none;cursor:inherit}.mw-parser-output .navbar-ct-full{font-size:114%;margin:0 7em}.mw-parser-output .navbar-ct-mini{font-size:114%;margin:0 4em}html.skin-theme-clientpref-night .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}@media(prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}}@media print{.mw-parser-output .navbar{display:none!important}}</style><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Classical_mechanics_SI_units" title="Template:Classical mechanics SI units"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Classical_mechanics_SI_units" title="Template talk:Classical mechanics SI units"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Classical_mechanics_SI_units" title="Special:EditPage/Template:Classical mechanics SI units"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Classical_mechanics_SI_units" style="font-size:114%;margin:0 4em"><a href="/wiki/Classical_mechanics" title="Classical mechanics">Classical mechanics</a> <a href="/wiki/International_System_of_Units" title="International System of Units">SI units</a></div></th></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0;"><table class="wikitable" style="text-align:center;line-height:0.9;border-collapse:collapse;margin:auto;border:none;background:none;"> <tbody><tr> <td colspan="4" style="border:none;backgound:none; font-weight:bold;">Linear/translational quantities</td> <td rowspan="12" style="border:none;backgound:none;"></td> <td colspan="4" style="border:none;backgound:none; font-weight:bold;">Angular/rotational quantities</td> </tr> <tr> <th style="font-weight:normal;font-size:80%;">Dimensions</th> <th style="font-weight:normal;">1</th> <th style="font-weight:normal;">L</th> <th style="font-weight:normal;">L<sup>2</sup></th> <th style="font-weight:normal;font-size:80%;">Dimensions</th> <th style="font-weight:normal;">1</th> <th style="font-weight:normal;"><span class="texhtml"><i>θ</i></span></th> <th style="font-weight:normal;"><span class="texhtml"><i>θ</i></span><sup>2</sup></th> </tr> <tr> <th style="font-weight:normal;">T</th> <td><a href="/wiki/Time" title="Time">time</a>: <span class="texhtml"><i>t</i></span><br /><a href="/wiki/Second" title="Second">s</a></td> <td><a href="/wiki/Absement" title="Absement">absement</a>: <span class="texhtml"><b>A</b></span><br /><a href="/wiki/Meter_second" class="mw-redirect" title="Meter second">m s</a></td> <td></td> <th style="font-weight:normal;">T</th> <td><a href="/wiki/Time" title="Time">time</a>: <span class="texhtml"><i>t</i></span><br /><a href="/wiki/Second" title="Second">s</a></td> <td></td> <td></td> </tr> <tr> <th style="font-weight:normal;">1</th> <td></td> <td><a href="/wiki/Distance" title="Distance">distance</a>: <span class="texhtml"><i>d</i></span>, <span class="nowrap"><a href="/wiki/Position_(vector)" class="mw-redirect" title="Position (vector)">position</a>: <span class="texhtml"><b>r</b></span>, <span class="texhtml"><b>s</b></span>, <span class="texhtml"><b>x</b></span></span>, <a href="/wiki/Displacement_(vector)" class="mw-redirect" title="Displacement (vector)">displacement</a><br /><a href="/wiki/Metre" title="Metre">m</a></td> <td><a class="mw-selflink selflink">area</a>: <span class="texhtml"><i>A</i></span><br /><a href="/wiki/Square_metre" title="Square metre">m<sup>2</sup></a></td> <th style="font-weight:normal;">1</th> <td></td> <td><a href="/wiki/Angle" title="Angle">angle</a>: <span class="texhtml"><i>θ</i></span>, <a href="/wiki/Angular_displacement" title="Angular displacement">angular displacement</a>: <span class="texhtml"><i><b>θ</b></i></span><br /><a href="/wiki/Radian" title="Radian">rad</a></td> <td><span class="nowrap"><a href="/wiki/Solid_angle" title="Solid angle">solid angle</a>: <span class="texhtml">Ω</span><br /><a href="/wiki/Steradian" title="Steradian">rad<sup>2</sup>, sr</a></span></td> </tr> <tr> <th style="font-weight:normal;">T<sup>−1</sup></th> <td><span class="nowrap"><a href="/wiki/Frequency" title="Frequency">frequency</a>: <span class="texhtml"><i>f</i></span></span><br /><a href="/wiki/Inverse_second" title="Inverse second">s<sup>−1</sup></a>, <a href="/wiki/Hertz" title="Hertz">Hz</a></td> <td><a href="/wiki/Speed" title="Speed">speed</a>: <span class="texhtml"><i>v</i></span>, <a href="/wiki/Velocity" title="Velocity">velocity</a>: <span class="texhtml"><b>v</b></span><br /><a href="/wiki/Metre_per_second" title="Metre per second">m s<sup>−1</sup></a></td> <td><a href="/wiki/Kinematic_viscosity" class="mw-redirect" title="Kinematic viscosity">kinematic viscosity</a>: <span class="texhtml"><i>ν</i></span>,<br /><a href="/wiki/Specific_angular_momentum" title="Specific angular momentum">specific angular momentum</a>:&#160;<span class="texhtml"><b>h</b></span><br />m<sup>2</sup> s<sup>−1</sup></td> <th style="font-weight:normal;">T<sup>−1</sup></th> <td><span class="nowrap"><a href="/wiki/Frequency" title="Frequency">frequency</a>: <span class="texhtml"><i>f</i></span></span>, <span class="nowrap"><a href="/wiki/Rotational_speed" class="mw-redirect" title="Rotational speed">rotational speed</a>: <span class="texhtml"><i>n</i></span></span>, <span class="nowrap"><a href="/wiki/Rotational_velocity" class="mw-redirect" title="Rotational velocity">rotational velocity</a>: <span class="texhtml"><i><b>n</b></i></span></span><br /><a href="/wiki/Inverse_second" title="Inverse second">s<sup>−1</sup></a>, <a href="/wiki/Hertz" title="Hertz">Hz</a></td> <td><a href="/wiki/Angular_speed" class="mw-redirect" title="Angular speed">angular speed</a>: <span class="texhtml"><i>ω</i></span>, <a href="/wiki/Angular_velocity" title="Angular velocity">angular velocity</a>: <span class="texhtml"><i><b>ω</b></i></span><br /><a href="/wiki/Radian_per_second" title="Radian per second">rad<span style="letter-spacing:0.1em">&#160;</span>s<sup>−1</sup></a></td> <td></td> </tr> <tr> <th style="font-weight:normal;">T<sup>−2</sup></th> <td></td> <td><a href="/wiki/Acceleration" title="Acceleration">acceleration</a>: <span class="texhtml"><b>a</b></span><br /><a href="/wiki/Metre_per_second_squared" title="Metre per second squared">m s<sup>−2</sup></a></td> <td></td> <th style="font-weight:normal;">T<sup>−2</sup></th> <td><span class="nowrap"><a href="/wiki/Rotational_acceleration" class="mw-redirect" title="Rotational acceleration">rotational acceleration</a></span><br /><a href="/wiki/Inverse_square_second" class="mw-redirect" title="Inverse square second">s<sup>−2</sup></a></td> <td><a href="/wiki/Angular_acceleration" title="Angular acceleration">angular acceleration</a>: <span class="texhtml"><i><b>α</b></i></span><br /><a href="/wiki/Radian_per_second_squared" class="mw-redirect" title="Radian per second squared">rad<span style="letter-spacing:0.1em">&#160;</span>s<sup>−2</sup></a></td> <td></td> </tr> <tr> <th style="font-weight:normal;">T<sup>−3</sup></th> <td></td> <td><a href="/wiki/Jerk_(physics)" title="Jerk (physics)">jerk</a>: <span class="texhtml"><b>j</b></span><br />m s<sup>−3</sup></td> <td></td> <th style="font-weight:normal;">T<sup>−3</sup></th> <td></td> <td><a href="/wiki/Jerk_(physics)#Jerk_in_rotation" title="Jerk (physics)">angular jerk</a>: <span class="texhtml"><i><b>ζ</b></i></span><br />rad<span style="letter-spacing:0.1em">&#160;</span>s<sup>−3</sup></td> <td></td> </tr> <tr style="border-top: 3px double #a2a9b1;"> <th style="font-weight:normal;">M</th> <td><a href="/wiki/Mass" title="Mass">mass</a>: <span class="texhtml"><i>m</i></span><br /><a href="/wiki/Kilogram" title="Kilogram">kg</a></td> <td>weighted position: <span class="texhtml"><i>M</i> ⟨<i>x</i>⟩ = ∑ <i>m</i> <i>x</i></span> </td> <td></td> <th style="font-weight:normal;">ML<sup>2</sup></th> <td><a href="/wiki/Moment_of_inertia" title="Moment of inertia">moment of inertia</a>:&#160;<span class="texhtml"><i>I</i></span><br /><a href="/wiki/Kilogram_square_metre" class="mw-redirect" title="Kilogram square metre">kg<span style="letter-spacing:0.1em">&#160;</span>m<sup>2</sup></a></td> <td></td> <td></td> </tr> <tr> <th style="font-weight:normal;">MT<sup>−1</sup></th> <td><a href="/wiki/Mass_flow_rate" title="Mass flow rate">Mass flow rate</a>: <span class="texhtml"><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\dot {m}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mrow class="MJX-TeXAtom-ORD"> <mrow class="MJX-TeXAtom-ORD"> <mover> <mi>m</mi> <mo>&#x02D9;<!-- ˙ --></mo> </mover> </mrow> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle {\dot {m}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/ad59b9876301e8fb75b9ddbf08de594b87251d3b" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:2.04ex; height:2.176ex;" alt="{\displaystyle {\dot {m}}}"></span></span><br /><a href="/wiki/Kilogram_per_second" class="mw-redirect" title="Kilogram per second">kg<span style="letter-spacing:0.1em">&#160;</span>s<sup>−1</sup></a></td> <td><a href="/wiki/Momentum" title="Momentum">momentum</a>: <span class="texhtml"><b>p</b></span>, <a href="/wiki/Impulse_(physics)" title="Impulse (physics)">impulse</a>: <span class="texhtml"><b>J</b></span><br /><a href="/wiki/Kilogram_metre_per_second" class="mw-redirect" title="Kilogram metre per second">kg<span style="letter-spacing:0.1em">&#160;</span>m&#160;s<sup>−1</sup></a>, <a href="/wiki/Newton_second" class="mw-redirect" title="Newton second">N s</a></td> <td><a href="/wiki/Action_(physics)" title="Action (physics)">action</a>: <span class="texhtml">𝒮</span>, <a href="/wiki/Absement#Applications" title="Absement">actergy</a>: <span class="texhtml">ℵ</span><br /><a href="/wiki/Kilogram_square_metre_per_second" class="mw-redirect" title="Kilogram square metre per second">kg<span style="letter-spacing:0.1em">&#160;</span>m<sup>2</sup>&#160;s<sup>−1</sup></a>, <a href="/wiki/Joule-second" title="Joule-second">J s</a></td> <th style="font-weight:normal;">ML<sup>2</sup>T<sup>−1</sup></th> <td></td> <td><a href="/wiki/Angular_momentum" title="Angular momentum">angular momentum</a>: <span class="texhtml"><b>L</b></span>, <a href="/wiki/List_of_equations_in_classical_mechanics#Derived_dynamic_quantities" title="List of equations in classical mechanics">angular impulse</a>: <span class="texhtml">Δ<b>L</b></span><br /><a href="/wiki/Kilogram_square_metre_per_second" class="mw-redirect" title="Kilogram square metre per second">kg<span style="letter-spacing:0.1em">&#160;</span>m<sup>2</sup>&#160;s<sup>−1</sup></a></td> <td><a href="/wiki/Action_(physics)" title="Action (physics)">action</a>: <span class="texhtml">𝒮</span>, <a href="/wiki/Absement#Applications" title="Absement">actergy</a>: <span class="texhtml">ℵ</span><br /><a href="/wiki/Kilogram_square_metre_per_second" class="mw-redirect" title="Kilogram square metre per second">kg<span style="letter-spacing:0.1em">&#160;</span>m<sup>2</sup>&#160;s<sup>−1</sup></a>, <a href="/wiki/Joule-second" title="Joule-second">J&#160;s</a></td> </tr> <tr> <th style="font-weight:normal;">MT<sup>−2</sup></th> <td></td> <td><a href="/wiki/Force" title="Force">force</a>: <span class="texhtml"><b>F</b></span>, <a href="/wiki/Weight" title="Weight">weight</a>: <span class="texhtml"><b>F</b><sub>g</sub></span><br /><span style="margin-right:0.1em;">kg </span> m s<sup>−2</sup>, <a href="/wiki/Newton_(unit)" title="Newton (unit)">N</a></td> <td><a href="/wiki/Energy" title="Energy">energy</a>: <span class="texhtml"><i>E</i></span>, <a href="/wiki/Work_(physics)" title="Work (physics)">work</a>: <span class="texhtml"><i>W</i></span>, <a href="/wiki/Lagrangian_mechanics" title="Lagrangian mechanics">Lagrangian</a>: <span class="texhtml"><i>L</i></span><br /><span style="margin-right:0.1em;">kg</span> m<sup>2</sup> s<sup>−2</sup>, <a href="/wiki/Joule" title="Joule">J</a></td> <th style="font-weight:normal;">ML<sup>2</sup>T<sup>−2</sup></th> <td></td> <td><a href="/wiki/Torque" title="Torque">torque</a>: <span class="texhtml"><i><b>τ</b></i></span>, <a href="/wiki/Torque#Terminology" title="Torque">moment</a>: <span class="texhtml"><b>M</b></span><br /><span style="margin-right:0.1em;">kg</span> m<sup>2</sup> s<sup>−2</sup>, <a href="/wiki/Newton-metre" title="Newton-metre">N m</a></td> <td><a href="/wiki/Energy" title="Energy">energy</a>: <span class="texhtml"><i>E</i></span>, <a href="/wiki/Work_(physics)" title="Work (physics)">work</a>: <span class="texhtml"><i>W</i></span>, <a href="/wiki/Lagrangian_mechanics" title="Lagrangian mechanics">Lagrangian</a>: <span class="texhtml"><i>L</i></span><br /><span style="margin-right:0.1em;">kg</span> m<sup>2</sup> s<sup>−2</sup>, <a href="/wiki/Joule" title="Joule">J</a></td> </tr> <tr> <th style="font-weight:normal;">MT<sup>−3</sup></th> <td></td> <td><a href="/wiki/Yank_(physics)" class="mw-redirect" title="Yank (physics)">yank</a>: <span class="texhtml"><b>Y</b></span><br /><span style="margin-right:0.1em;">kg</span> m s<sup>−3</sup>, N s<sup>−1</sup></td> <td><a href="/wiki/Power_(physics)" title="Power (physics)">power</a>: <span class="texhtml"><i>P</i></span><br /><span style="margin-right:0.1em;">kg</span> m<sup>2</sup> s<sup>−3</sup>,&#160;<a href="/wiki/Watt" title="Watt">W</a></td> <th style="font-weight:normal;">ML<sup>2</sup>T<sup>−3</sup></th> <td></td> <td><a href="/wiki/Rotatum" class="mw-redirect" title="Rotatum">rotatum</a>: <span class="texhtml"><b>P</b></span><br /><span style="margin-right:0.1em;">kg</span> m<sup>2</sup> s<sup>−3</sup>, N m s<sup>−1</sup></td> <td><a href="/wiki/Power_(physics)" title="Power (physics)">power</a>: <span class="texhtml"><i>P</i></span><br /><span style="margin-right:0.1em;">kg</span> m<sup>2 </sup>s<sup>−3</sup>,&#160;<a href="/wiki/Watt" title="Watt">W</a></td> </tr> </tbody></table></div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"><style data-mw-deduplicate="TemplateStyles:r1038841319">.mw-parser-output .tooltip-dotted{border-bottom:1px dotted;cursor:help}</style><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1038841319"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1038841319"></div><div role="navigation" class="navbox authority-control" aria-label="Navbox" style="padding:3px"><table class="nowraplinks hlist navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Help:Authority_control" title="Help:Authority control">Authority control databases</a>: National <span class="mw-valign-text-top noprint" typeof="mw:File/Frameless"><a href="https://www.wikidata.org/wiki/Q11500#identifiers" title="Edit this at Wikidata"><img alt="Edit this at Wikidata" src="//upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/10px-OOjs_UI_icon_edit-ltr-progressive.svg.png" decoding="async" width="10" height="10" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/15px-OOjs_UI_icon_edit-ltr-progressive.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/20px-OOjs_UI_icon_edit-ltr-progressive.svg.png 2x" data-file-width="20" data-file-height="20" /></a></span></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"><ul><li><span class="uid"><a rel="nofollow" class="external text" href="https://d-nb.info/gnd/4193807-0">Germany</a></span></li><li><span class="uid"><span class="rt-commentedText tooltip tooltip-dotted" title="Area measurement"><a rel="nofollow" class="external text" href="https://id.loc.gov/authorities/sh85006984">United States</a></span></span></li><li><span class="uid"><span class="rt-commentedText tooltip tooltip-dotted" title="Surfaces (mathématiques) -- Mesure"><a rel="nofollow" class="external text" href="https://catalogue.bnf.fr/ark:/12148/cb12172891w">France</a></span></span></li><li><span class="uid"><span class="rt-commentedText tooltip tooltip-dotted" title="Surfaces (mathématiques) -- Mesure"><a rel="nofollow" class="external text" href="https://data.bnf.fr/ark:/12148/cb12172891w">BnF data</a></span></span></li><li><span class="uid"><a rel="nofollow" class="external text" href="http://olduli.nli.org.il/F/?func=find-b&amp;local_base=NLX10&amp;find_code=UID&amp;request=987007295555305171">Israel</a></span></li></ul></div></td></tr></tbody></table></div> <!-- NewPP limit report Parsed by mw‐web.codfw.main‐f69cdc8f6‐78s75 Cached time: 20241122141357 Cache expiry: 2592000 Reduced expiry: false Complications: [vary‐revision‐sha1, show‐toc] CPU time usage: 1.159 seconds Real time usage: 1.625 seconds Preprocessor visited node count: 7666/1000000 Post‐expand include size: 122037/2097152 bytes Template argument size: 7681/2097152 bytes Highest expansion depth: 16/100 Expensive parser function count: 13/500 Unstrip recursion depth: 1/20 Unstrip post‐expand size: 152793/5000000 bytes Lua time usage: 0.639/10.000 seconds Lua memory usage: 8221366/52428800 bytes Number of Wikibase entities loaded: 1/400 --> <!-- Transclusion expansion time report (%,ms,calls,template) 100.00% 1153.577 1 -total 31.43% 362.602 1 Template:Reflist 13.40% 154.603 1 Template:Classical_mechanics_derived_SI_units 13.04% 150.444 1 Template:Navbox 12.84% 148.108 12 Template:Cite_web 12.13% 139.874 1 Template:Sister_project_links 9.36% 107.964 1 Template:Infobox_physical_quantity 9.09% 104.902 1 Template:Infobox 8.75% 100.990 1 Template:Short_description 7.42% 85.568 1 Template:Excerpt --> <!-- Saved in parser cache with key enwiki:pcache:idhash:1209-0!canonical and timestamp 20241122141357 and revision id 1255146594. Rendering was triggered because: page-view --> </div><!--esi <esi:include src="/esitest-fa8a495983347898/content" /> --><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikipedia.org/w/index.php?title=Area&amp;oldid=1255146594">https://en.wikipedia.org/w/index.php?title=Area&amp;oldid=1255146594</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Help:Category" title="Help:Category">Category</a>: <ul><li><a href="/wiki/Category:Area" title="Category:Area">Area</a></li></ul></div><div id="mw-hidden-catlinks" class="mw-hidden-catlinks mw-hidden-cats-hidden">Hidden categories: <ul><li><a href="/wiki/Category:CS1:_long_volume_value" title="Category:CS1: long volume value">CS1: long volume value</a></li><li><a href="/wiki/Category:Articles_with_short_description" title="Category:Articles with short description">Articles with short description</a></li><li><a href="/wiki/Category:Short_description_is_different_from_Wikidata" title="Category:Short description is different from Wikidata">Short description is different from Wikidata</a></li><li><a href="/wiki/Category:Wikipedia_indefinitely_move-protected_pages" title="Category:Wikipedia indefinitely move-protected pages">Wikipedia indefinitely move-protected pages</a></li><li><a href="/wiki/Category:Articles_with_excerpts" title="Category:Articles with excerpts">Articles with excerpts</a></li><li><a href="/wiki/Category:Pages_using_Sister_project_links_with_hidden_wikidata" title="Category:Pages using Sister project links with hidden wikidata">Pages using Sister project links with hidden wikidata</a></li><li><a href="/wiki/Category:Pages_using_Sister_project_links_with_default_search" title="Category:Pages using Sister project links with default search">Pages using Sister project links with default search</a></li></ul></div></div> </div> </main> </div> <div class="mw-footer-container"> <footer id="footer" class="mw-footer" > <ul id="footer-info"> <li id="footer-info-lastmod"> This page was last edited on 3 November 2024, at 11:16<span class="anonymous-show">&#160;(UTC)</span>.</li> <li id="footer-info-copyright">Text is available under the <a href="/wiki/Wikipedia:Text_of_the_Creative_Commons_Attribution-ShareAlike_4.0_International_License" title="Wikipedia:Text of the Creative Commons Attribution-ShareAlike 4.0 International License">Creative Commons Attribution-ShareAlike 4.0 License</a>; additional terms may apply. By using this site, you agree to the <a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Terms_of_Use" class="extiw" title="foundation:Special:MyLanguage/Policy:Terms of Use">Terms of Use</a> and <a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy" class="extiw" title="foundation:Special:MyLanguage/Policy:Privacy policy">Privacy Policy</a>. Wikipedia® is a registered trademark of the <a rel="nofollow" class="external text" href="https://wikimediafoundation.org/">Wikimedia Foundation, Inc.</a>, a non-profit organization.</li> </ul> <ul id="footer-places"> <li id="footer-places-privacy"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy">Privacy policy</a></li> <li id="footer-places-about"><a href="/wiki/Wikipedia:About">About Wikipedia</a></li> <li id="footer-places-disclaimers"><a href="/wiki/Wikipedia:General_disclaimer">Disclaimers</a></li> <li id="footer-places-contact"><a href="//en.wikipedia.org/wiki/Wikipedia:Contact_us">Contact Wikipedia</a></li> <li id="footer-places-wm-codeofconduct"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Universal_Code_of_Conduct">Code of Conduct</a></li> <li id="footer-places-developers"><a href="https://developer.wikimedia.org">Developers</a></li> <li id="footer-places-statslink"><a href="https://stats.wikimedia.org/#/en.wikipedia.org">Statistics</a></li> <li id="footer-places-cookiestatement"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Cookie_statement">Cookie statement</a></li> <li id="footer-places-mobileview"><a href="//en.m.wikipedia.org/w/index.php?title=Area&amp;mobileaction=toggle_view_mobile" class="noprint stopMobileRedirectToggle">Mobile view</a></li> </ul> <ul id="footer-icons" class="noprint"> <li id="footer-copyrightico"><a href="https://wikimediafoundation.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><img src="/static/images/footer/wikimedia-button.svg" width="84" height="29" alt="Wikimedia Foundation" loading="lazy"></a></li> <li id="footer-poweredbyico"><a href="https://www.mediawiki.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><img src="/w/resources/assets/poweredby_mediawiki.svg" alt="Powered by MediaWiki" width="88" height="31" loading="lazy"></a></li> </ul> </footer> </div> </div> </div> <div class="vector-settings" id="p-dock-bottom"> <ul></ul> </div><script>(RLQ=window.RLQ||[]).push(function(){mw.config.set({"wgHostname":"mw-web.codfw.main-f69cdc8f6-mjpz6","wgBackendResponseTime":193,"wgPageParseReport":{"limitreport":{"cputime":"1.159","walltime":"1.625","ppvisitednodes":{"value":7666,"limit":1000000},"postexpandincludesize":{"value":122037,"limit":2097152},"templateargumentsize":{"value":7681,"limit":2097152},"expansiondepth":{"value":16,"limit":100},"expensivefunctioncount":{"value":13,"limit":500},"unstrip-depth":{"value":1,"limit":20},"unstrip-size":{"value":152793,"limit":5000000},"entityaccesscount":{"value":1,"limit":400},"timingprofile":["100.00% 1153.577 1 -total"," 31.43% 362.602 1 Template:Reflist"," 13.40% 154.603 1 Template:Classical_mechanics_derived_SI_units"," 13.04% 150.444 1 Template:Navbox"," 12.84% 148.108 12 Template:Cite_web"," 12.13% 139.874 1 Template:Sister_project_links"," 9.36% 107.964 1 Template:Infobox_physical_quantity"," 9.09% 104.902 1 Template:Infobox"," 8.75% 100.990 1 Template:Short_description"," 7.42% 85.568 1 Template:Excerpt"]},"scribunto":{"limitreport-timeusage":{"value":"0.639","limit":"10.000"},"limitreport-memusage":{"value":8221366,"limit":52428800}},"cachereport":{"origin":"mw-web.codfw.main-f69cdc8f6-78s75","timestamp":"20241122141357","ttl":2592000,"transientcontent":false}}});});</script> <script type="application/ld+json">{"@context":"https:\/\/schema.org","@type":"Article","name":"Area","url":"https:\/\/en.wikipedia.org\/wiki\/Area","sameAs":"http:\/\/www.wikidata.org\/entity\/Q11500","mainEntity":"http:\/\/www.wikidata.org\/entity\/Q11500","author":{"@type":"Organization","name":"Contributors to Wikimedia projects"},"publisher":{"@type":"Organization","name":"Wikimedia Foundation, Inc.","logo":{"@type":"ImageObject","url":"https:\/\/www.wikimedia.org\/static\/images\/wmf-hor-googpub.png"}},"datePublished":"2002-02-25T15:43:11Z","dateModified":"2024-11-03T11:16:14Z","image":"https:\/\/upload.wikimedia.org\/wikipedia\/commons\/a\/a7\/Squaring_the_circle.svg","headline":"quantity that expresses the extent of a two-dimensional surface or shape, or planar lamina, in the plane"}</script> </body> </html>

Pages: 1 2 3 4 5 6 7 8 9 10