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Disponible en 38 llengües" > <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-38" 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">38 llengües</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D9%85%D9%88%D9%82%D8%B9_%D9%85%D8%A7%D8%AB%D9%88%D9%88%D8%B1%D9%84%D8%AF" title="موقع ماثوورلد - àrab" lang="ar" hreflang="ar" data-title="موقع ماثوورلد" data-language-autonym="العربية" data-language-local-name="àrab" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/MathWorld" title="MathWorld - búlgar" lang="bg" hreflang="bg" data-title="MathWorld" data-language-autonym="Български" data-language-local-name="búlgar" class="interlanguage-link-target"><span>Български</span></a></li><li class="interlanguage-link interwiki-bn mw-list-item"><a href="https://bn.wikipedia.org/wiki/%E0%A6%AE%E0%A7%8D%E0%A6%AF%E0%A6%BE%E0%A6%A5%E0%A6%93%E0%A6%AF%E0%A6%BC%E0%A6%BE%E0%A6%B0%E0%A7%8D%E0%A6%B2%E0%A7%8D%E0%A6%A1" title="ম্যাথওয়ার্ল্ড - bengalí" lang="bn" hreflang="bn" data-title="ম্যাথওয়ার্ল্ড" data-language-autonym="বাংলা" data-language-local-name="bengalí" class="interlanguage-link-target"><span>বাংলা</span></a></li><li class="interlanguage-link interwiki-ckb mw-list-item"><a href="https://ckb.wikipedia.org/wiki/%D9%85%D8%A7%D8%AA%D9%88%DB%86%D8%B1%DA%B5%D8%AF" title="ماتوۆرڵد - kurd central" lang="ckb" hreflang="ckb" data-title="ماتوۆرڵد" data-language-autonym="کوردی" data-language-local-name="kurd central" class="interlanguage-link-target"><span>کوردی</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/MathWorld" title="MathWorld - txec" lang="cs" hreflang="cs" data-title="MathWorld" data-language-autonym="Čeština" data-language-local-name="txec" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/MathWorld" title="MathWorld - alemany" lang="de" hreflang="de" data-title="MathWorld" data-language-autonym="Deutsch" data-language-local-name="alemany" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-el mw-list-item"><a href="https://el.wikipedia.org/wiki/MathWorld" title="MathWorld - grec" lang="el" hreflang="el" data-title="MathWorld" data-language-autonym="Ελληνικά" data-language-local-name="grec" class="interlanguage-link-target"><span>Ελληνικά</span></a></li><li class="interlanguage-link interwiki-en mw-list-item"><a href="https://en.wikipedia.org/wiki/MathWorld" title="MathWorld - anglès" lang="en" hreflang="en" data-title="MathWorld" data-language-autonym="English" data-language-local-name="anglès" class="interlanguage-link-target"><span>English</span></a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/MathWorld" title="MathWorld - esperanto" lang="eo" hreflang="eo" data-title="MathWorld" data-language-autonym="Esperanto" data-language-local-name="esperanto" class="interlanguage-link-target"><span>Esperanto</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/MathWorld" title="MathWorld - espanyol" lang="es" hreflang="es" data-title="MathWorld" data-language-autonym="Español" data-language-local-name="espanyol" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/MathWorld" title="MathWorld - basc" lang="eu" hreflang="eu" data-title="MathWorld" data-language-autonym="Euskara" data-language-local-name="basc" 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%AB%E2%80%8C%D9%88%D8%B1%D9%84%D8%AF" title="مث‌ورلد - persa" lang="fa" hreflang="fa" data-title="مث‌ورلد" data-language-autonym="فارسی" data-language-local-name="persa" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/MathWorld" title="MathWorld - finès" lang="fi" hreflang="fi" data-title="MathWorld" data-language-autonym="Suomi" data-language-local-name="finès" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/MathWorld" title="MathWorld - francès" lang="fr" hreflang="fr" data-title="MathWorld" data-language-autonym="Français" data-language-local-name="francès" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-gl mw-list-item"><a href="https://gl.wikipedia.org/wiki/MathWorld" title="MathWorld - gallec" lang="gl" hreflang="gl" data-title="MathWorld" data-language-autonym="Galego" data-language-local-name="gallec" class="interlanguage-link-target"><span>Galego</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/MathWorld" title="MathWorld - hebreu" lang="he" hreflang="he" data-title="MathWorld" data-language-autonym="עברית" data-language-local-name="hebreu" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%AE%E0%A5%88%E0%A4%A5%E0%A4%B5%E0%A4%B0%E0%A5%8D%E0%A4%B2%E0%A5%8D%E0%A4%A1" title="मैथवर्ल्ड - hindi" lang="hi" hreflang="hi" data-title="मैथवर्ल्ड" data-language-autonym="हिन्दी" data-language-local-name="hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/MathWorld" title="MathWorld - hongarès" lang="hu" hreflang="hu" data-title="MathWorld" data-language-autonym="Magyar" data-language-local-name="hongarès" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/MathWorld" title="MathWorld - indonesi" lang="id" hreflang="id" data-title="MathWorld" data-language-autonym="Bahasa Indonesia" data-language-local-name="indonesi" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/MathWorld" title="MathWorld - italià" lang="it" hreflang="it" data-title="MathWorld" data-language-autonym="Italiano" data-language-local-name="italià" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/MathWorld" title="MathWorld - japonès" lang="ja" hreflang="ja" data-title="MathWorld" data-language-autonym="日本語" data-language-local-name="japonès" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EB%A7%A4%EC%8A%A4%EC%9B%94%EB%93%9C" title="매스월드 - coreà" lang="ko" hreflang="ko" data-title="매스월드" data-language-autonym="한국어" data-language-local-name="coreà" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-mk mw-list-item"><a href="https://mk.wikipedia.org/wiki/MathWorld" title="MathWorld - macedoni" lang="mk" hreflang="mk" data-title="MathWorld" data-language-autonym="Македонски" data-language-local-name="macedoni" class="interlanguage-link-target"><span>Македонски</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/MathWorld" title="MathWorld - malai" lang="ms" hreflang="ms" data-title="MathWorld" data-language-autonym="Bahasa Melayu" data-language-local-name="malai" class="interlanguage-link-target"><span>Bahasa Melayu</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/MathWorld" title="MathWorld - neerlandès" lang="nl" hreflang="nl" data-title="MathWorld" data-language-autonym="Nederlands" data-language-local-name="neerlandès" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/MathWorld" title="MathWorld - noruec bokmål" lang="nb" hreflang="nb" data-title="MathWorld" data-language-autonym="Norsk bokmål" data-language-local-name="noruec bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/MathWorld" title="MathWorld - polonès" lang="pl" hreflang="pl" data-title="MathWorld" data-language-autonym="Polski" data-language-local-name="polonès" 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/MathWorld" title="MathWorld - portuguès" lang="pt" hreflang="pt" data-title="MathWorld" data-language-autonym="Português" data-language-local-name="portuguès" 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/MathWorld" title="MathWorld - romanès" lang="ro" hreflang="ro" data-title="MathWorld" data-language-autonym="Română" data-language-local-name="romanès" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/MathWorld" title="MathWorld - rus" lang="ru" hreflang="ru" data-title="MathWorld" data-language-autonym="Русский" data-language-local-name="rus" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-sl mw-list-item"><a href="https://sl.wikipedia.org/wiki/MathWorld" title="MathWorld - eslovè" lang="sl" hreflang="sl" data-title="MathWorld" data-language-autonym="Slovenščina" data-language-local-name="eslovè" class="interlanguage-link-target"><span>Slovenščina</span></a></li><li class="interlanguage-link interwiki-su mw-list-item"><a href="https://su.wikipedia.org/wiki/MathWorld" title="MathWorld - sondanès" lang="su" hreflang="su" data-title="MathWorld" data-language-autonym="Sunda" data-language-local-name="sondanès" class="interlanguage-link-target"><span>Sunda</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Mathworld" title="Mathworld - suec" lang="sv" hreflang="sv" data-title="Mathworld" data-language-autonym="Svenska" data-language-local-name="suec" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B9%81%E0%B8%A1%E0%B8%97%E0%B9%80%E0%B8%A7%E0%B8%B4%E0%B8%A5%E0%B8%94%E0%B9%8C" title="แมทเวิลด์ - tai" lang="th" hreflang="th" data-title="แมทเวิลด์" data-language-autonym="ไทย" data-language-local-name="tai" class="interlanguage-link-target"><span>ไทย</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/MathWorld" title="MathWorld - turc" lang="tr" hreflang="tr" data-title="MathWorld" data-language-autonym="Türkçe" data-language-local-name="turc" 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/MathWorld" title="MathWorld - ucraïnès" lang="uk" hreflang="uk" data-title="MathWorld" data-language-autonym="Українська" data-language-local-name="ucraïnès" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/MathWorld" title="MathWorld - vietnamita" lang="vi" hreflang="vi" data-title="MathWorld" data-language-autonym="Tiếng Việt" data-language-local-name="vietnamita" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/MathWorld" title="MathWorld - xinès" lang="zh" hreflang="zh" data-title="MathWorld" data-language-autonym="中文" data-language-local-name="xinès" class="interlanguage-link-target"><span>中文</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/Q719112#sitelinks-wikipedia" title="Modifica enllaços interlingües" class="wbc-editpage">Modifica els enllaços</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="Espais de noms"> <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/MathWorld" title="Vegeu el contingut de la pàgina [c]" accesskey="c"><span>Pàgina</span></a></li><li id="ca-talk" class="vector-tab-noicon mw-list-item"><a href="/wiki/Discussi%C3%B3:MathWorld" rel="discussion" title="Discussió sobre el contingut d'aquesta pàgina [t]" accesskey="t"><span>Discussió</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="Canvia la variant de llengua" > <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">català</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="Vistes"> <div id="p-views" class="vector-menu vector-menu-tabs mw-portlet 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<button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-appearance.pin">mou a la barra lateral</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-appearance.unpin">amaga</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">De la Viquipèdia, l'enciclopèdia lliure</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="ca" dir="ltr"><table class="infobox" style="font-size:90%;width:25em"><caption style="font-weight:bold;background:Moccasin;"><span style="float:left;"><span typeof="mw:File"><span title="Infotaula de lloc web"><img alt="Infotaula de lloc web" src="//upload.wikimedia.org/wikipedia/commons/thumb/5/56/Antu_tag-places-black.svg/23px-Antu_tag-places-black.svg.png" decoding="async" width="23" height="23" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/56/Antu_tag-places-black.svg/35px-Antu_tag-places-black.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/56/Antu_tag-places-black.svg/46px-Antu_tag-places-black.svg.png 2x" data-file-width="18" data-file-height="18" /></span></span></span>MathWorld</caption><tbody><tr><th scope="row" class="infobox-label" style="text-align:left;padding-right:1.2em; background:#eeeeee; text-align:start"><a href="/wiki/Localitzador_uniforme_de_recursos" title="Localitzador uniforme de recursos">URL</a></th><td class="infobox-data" style="text-align:start"><a rel="nofollow" class="external free" href="https://mathworld.wolfram.com">https://mathworld.wolfram.com</a> <span class="penicon"><span class="mw-valign-baseline" typeof="mw:File"><a href="https://www.wikidata.org/wiki/Q719112?uselang=ca#P856" title="Modifica el valor a Wikidata"><img alt="Modifica el valor a Wikidata" src="//upload.wikimedia.org/wikipedia/commons/thumb/6/63/Arbcom_ru_editing.svg/10px-Arbcom_ru_editing.svg.png" decoding="async" width="10" height="10" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/63/Arbcom_ru_editing.svg/15px-Arbcom_ru_editing.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/63/Arbcom_ru_editing.svg/20px-Arbcom_ru_editing.svg.png 2x" data-file-width="600" data-file-height="600" /></a></span></span></td></tr><tr><th scope="row" class="infobox-label" style="text-align:left;padding-right:1.2em; background:#eeeeee; text-align:start">Tipus</th><td class="infobox-data" style="text-align:start"><a href="/wiki/Enciclop%C3%A8dia_en_l%C3%ADnia" title="Enciclopèdia en línia">enciclopèdia en línia</a> <span class="penicon"><span class="mw-valign-baseline" typeof="mw:File"><a href="https://www.wikidata.org/wiki/Q719112?uselang=ca#P31" title="Modifica el valor a Wikidata"><img alt="Modifica el valor a Wikidata" src="//upload.wikimedia.org/wikipedia/commons/thumb/6/63/Arbcom_ru_editing.svg/10px-Arbcom_ru_editing.svg.png" decoding="async" width="10" height="10" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/63/Arbcom_ru_editing.svg/15px-Arbcom_ru_editing.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/63/Arbcom_ru_editing.svg/20px-Arbcom_ru_editing.svg.png 2x" data-file-width="600" data-file-height="600" /></a></span></span></td></tr><tr><th scope="row" class="infobox-label" style="text-align:left;padding-right:1.2em; background:#eeeeee; text-align:start">Llengua</th><td class="infobox-data" style="text-align:start"><a href="/wiki/Angl%C3%A8s" title="Anglès">anglès</a> <span class="penicon"><span class="mw-valign-baseline" typeof="mw:File"><a href="https://www.wikidata.org/wiki/Q719112?uselang=ca#P407" title="Modifica el valor a Wikidata"><img alt="Modifica el valor a Wikidata" src="//upload.wikimedia.org/wikipedia/commons/thumb/6/63/Arbcom_ru_editing.svg/10px-Arbcom_ru_editing.svg.png" decoding="async" width="10" height="10" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/63/Arbcom_ru_editing.svg/15px-Arbcom_ru_editing.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/63/Arbcom_ru_editing.svg/20px-Arbcom_ru_editing.svg.png 2x" data-file-width="600" data-file-height="600" /></a></span></span></td></tr><tr><th scope="row" class="infobox-label" style="text-align:left;padding-right:1.2em; background:#eeeeee; text-align:start">Propietari</th><td class="infobox-data" style="text-align:start"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q1367937" class="extiw" title="d:Special:EntityPage/Q1367937">Wolfram Research</a> <span class="penicon"><span class="mw-valign-baseline" typeof="mw:File"><a href="https://www.wikidata.org/wiki/Q719112?uselang=ca#P127" title="Modifica el valor a Wikidata"><img alt="Modifica el valor a Wikidata" src="//upload.wikimedia.org/wikipedia/commons/thumb/6/63/Arbcom_ru_editing.svg/10px-Arbcom_ru_editing.svg.png" decoding="async" width="10" height="10" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/63/Arbcom_ru_editing.svg/15px-Arbcom_ru_editing.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/63/Arbcom_ru_editing.svg/20px-Arbcom_ru_editing.svg.png 2x" data-file-width="600" data-file-height="600" /></a></span></span></td></tr><tr><th scope="row" class="infobox-label" style="text-align:left;padding-right:1.2em; background:#eeeeee; text-align:start">Creador</th><td class="infobox-data" style="text-align:start"><a href="/wiki/Eric_Weisstein" title="Eric Weisstein">Eric Weisstein</a> <span class="penicon"><span class="mw-valign-baseline" typeof="mw:File"><a href="https://www.wikidata.org/wiki/Q719112?uselang=ca#P112" title="Modifica el valor a Wikidata"><img alt="Modifica el valor a Wikidata" src="//upload.wikimedia.org/wikipedia/commons/thumb/6/63/Arbcom_ru_editing.svg/10px-Arbcom_ru_editing.svg.png" decoding="async" width="10" height="10" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/63/Arbcom_ru_editing.svg/15px-Arbcom_ru_editing.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/63/Arbcom_ru_editing.svg/20px-Arbcom_ru_editing.svg.png 2x" data-file-width="600" data-file-height="600" /></a></span></span></td></tr><tr><th scope="row" class="infobox-label" style="text-align:left;padding-right:1.2em; background:#eeeeee; text-align:start">Llançament</th><td class="infobox-data" style="text-align:start">novembre 1999 <span class="penicon"><span class="mw-valign-baseline" typeof="mw:File"><a href="https://www.wikidata.org/wiki/Q719112?uselang=ca#P571" title="Modifica el valor a Wikidata"><img alt="Modifica el valor a Wikidata" src="//upload.wikimedia.org/wikipedia/commons/thumb/6/63/Arbcom_ru_editing.svg/10px-Arbcom_ru_editing.svg.png" decoding="async" width="10" height="10" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/63/Arbcom_ru_editing.svg/15px-Arbcom_ru_editing.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/63/Arbcom_ru_editing.svg/20px-Arbcom_ru_editing.svg.png 2x" data-file-width="600" data-file-height="600" /></a></span></span></td></tr></tbody></table> <p><b>MathWorld</b> és una enciclopèdia matemàtica de referència, finançada per <a href="/w/index.php?title=Wolfram_Research&action=edit&redlink=1" class="new" title="Wolfram Research (encara no existeix)">Wolfram Research</a> Inc., els creadors del programari d'àlgebra computacional <a href="/wiki/Mathematica" title="Mathematica">Mathematica</a>. També està parcialment finançada per una beca de la <a href="/wiki/National_Science_Foundation" title="National Science Foundation">National Science Foundation</a> dels <a href="/wiki/Estats_Units_d%27Am%C3%A8rica" title="Estats Units d'Amèrica">Estats Units</a> a la <a href="/wiki/Universitat_d%27Illinois_a_Urbana-Champaign" title="Universitat d'Illinois a Urbana-Champaign">Universitat d'Illinois a Urbana-Champaign</a>. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Història"><span id="Hist.C3.B2ria"></span>Història</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=MathWorld&action=edit&section=1" title="Modifica la secció: Història"><span>modifica</span></a><span class="mw-editsection-bracket">]</span></span></div> <p><a href="/wiki/Eric_W._Weisstein" class="mw-redirect" title="Eric W. Weisstein">Eric W. Weisstein</a>, el creador de la pàgina, era un estudiant de <a href="/wiki/F%C3%ADsica" title="Física">física</a> i <a href="/wiki/Astronomia" title="Astronomia">astronomia</a> que es va acostumar a prendre apunts en els cursos de matemàtiques que rebia. En <a href="/wiki/1995" title="1995">1995</a> els va publicar en Internet sota el títol en anglès <i>"Eric's Treasure Trove of Mathematics"</i>. Contenia centenars de pàgines i articles sobre un ampli rang de temes matemàtics. La pàgina es va popularitzar en proporcionar una referència extensa sobre molts temes rellevants. Weisstein va continuar millorant les notes i acceptant correccions i comentaris dels seus lectors. En <a href="/wiki/1998" title="1998">1998</a>, va firmar un contracte amb CRC Press i els continguts de la pàgina web van ser publicats en paper i CD-Rom, titulats <i>"CRC Concise Encyclopedia of Mathematics"</i>. La versió gratuïta online va passar a ser només parcialment accessible al públic. En <a href="/wiki/1999" title="1999">1999</a> Weisstein va ser contractat per <a href="/w/index.php?title=Wolfram_Research&action=edit&redlink=1" class="new" title="Wolfram Research (encara no existeix)">Wolfram Research</a>, Inc. (WRI), i WRI va rebatejar el Math Treasure Trove com a <i>MathWorld</i>, accessible a <a rel="nofollow" class="external text" href="http://mathworld.wolfram.com">mathworld.wolfram.com</a>, i allotjat en la pàgina web de la companyia lliure de cost. </p> <div class="mw-heading mw-heading2"><h2 id="Crítiques"><span id="Cr.C3.ADtiques"></span>Crítiques</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=MathWorld&action=edit&section=2" title="Modifica la secció: Crítiques"><span>modifica</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>En el grup <a href="/wiki/Usenet" title="Usenet">Usenet</a> <tt><a href="/w/index.php?title=Sci.math&action=edit&redlink=1" class="new" title="Sci.math (encara no existeix)">sci.math</a></tt>, hi ha hagut comentaris sobre la qualitat dels articles de MathWorld. Si bé la informació en MathWorld és considerada generalment correcta, s'han trobat algunes afirmacions que són incorrectes o tenen problemes sintàctics.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p><p>Mathworld té una funcionalitat que permet que els lectors publiquin comentaris en articles individuals. No es coneixen estudis sistemàtics sobre la consistència de MathWorld, així com tampoc d'altres fonts de recursos matemàtics en línia, incloent la mateixa Wikipedia, per la qual cosa la qualitat és un tema que roman en debat i discussió. </p> <div class="mw-heading mw-heading2"><h2 id="Vegeu_també"><span id="Vegeu_tamb.C3.A9"></span>Vegeu també</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=MathWorld&action=edit&section=3" title="Modifica la secció: Vegeu també"><span>modifica</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/PlanetMath" title="PlanetMath">PlanetMath</a></li> <li><a href="/w/index.php?title=ScienceWorld&action=edit&redlink=1" class="new" title="ScienceWorld (encara no existeix)">ScienceWorld</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="Referències"><span id="Refer.C3.A8ncies"></span>Referències</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=MathWorld&action=edit&section=4" title="Modifica la secció: Referències"><span>modifica</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="reflist" style="list-style-type: decimal;"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><a href="#cite_ref-1">↑</a></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://groups.google.cat/groups?selm=uFp8d.631408$gE.26496@pd7tw3no">Entrada en sci.math</a><sup class="noprint Inline-Template"><span title=" since d’abril 2024" style="white-space: nowrap;"><i>[<a href="/wiki/Viquip%C3%A8dia:Enlla%C3%A7os_externs#Manteniment_d'enllaços_externs" title="Viquipèdia:Enllaços externs">Enllaç no actiu</a>]</i></span></sup> confusió a Mathworld sobre un terme</span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><a href="#cite_ref-2">↑</a></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://groups.google.cat/groups?selm=24fe76d6.0411291438.145f2e08@posting.google.com">Entrada en sci.math</a><sup class="noprint Inline-Template"><span title=" since d’abril 2024" style="white-space: nowrap;"><i>[<a href="/wiki/Viquip%C3%A8dia:Enlla%C3%A7os_externs#Manteniment_d'enllaços_externs" title="Viquipèdia:Enllaços externs">Enllaç no actiu</a>]</i></span></sup> errors de tipografia i ortografia a Mathworld</span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="Enllaços_externs"><span id="Enlla.C3.A7os_externs"></span>Enllaços externs</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=MathWorld&action=edit&section=5" title="Modifica la secció: Enllaços externs"><span>modifica</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a rel="nofollow" class="external text" href="http://mathworld.wolfram.com">Wolfram Research's MathWorld</a></li> <li><a rel="nofollow" class="external text" href="http://mathworld.wolfram.com/about/erics_commentary.html">Eric Weisstein's account of the suit</a></li></ul>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?useformat=desktop&type=1x1&usesul3=0" alt="" width="1" height="1" style="border: none; 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