Diagram showing the circumference <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 C}"><semantics><mrow class="MJX-TeXAtom-ORD"><mstyle displaystyle="true" scriptlevel="0"><mi>C</mi></mstyle></mrow><annotation encoding="application/x-tex">{\displaystyle C}</annotation></semantics></math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/4fc55753007cd3c18576f7933f6f089196732029" class="mwe-math-fallback-image-inline" aria-hidden="true" style="vertical-align: -0.338ex; width:1.766ex; height:2.176ex;" alt="{\displaystyle C}"></span> and diameter <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/e85ff03cbe0c7341af6b982e47e9f90d235c66ab" class="mwe-math-fallback-image-inline" aria-hidden="true" style="vertical-align: -0.338ex; width:1.216ex; height:2.176ex;" alt="{\displaystyle d}"></span> of a circle.
<a href="//commons.wikimedia.org/wiki/User:Kjoonlee" title="User:Kjoonlee">Kjoonlee</a>
2007-07-08
Own work based on: <span style="border:1px dotted #FC0;padding:0 4px"><a href="https://en.wikipedia.org/wiki/File:Pi.eq.C.over.d.png" class="extiw" title="en:File:Pi.eq.C.over.d.png">Pi.eq.C.over.d.png</a></span> <i>by</i> <a href="//commons.wikimedia.org/w/index.php?title=User:Papeschr&amp;action=edit&amp;redlink=1" class="new" title="User:Papeschr (page does not exist)">Papeschr</a>