Plot of the <a href="https://en.wikipedia.org/wiki/Euler_spiral" class="extiw" title="en:Euler spiral">Euler spiral</a>, Cornu spiral or clothoid:
<ul><li><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=C(t)}"><semantics><mrow class="MJX-TeXAtom-ORD"><mstyle displaystyle="true" scriptlevel="0"><mi>x</mi><mo>=</mo><mi>C</mi><mo stretchy="false">(</mo><mi>t</mi><mo stretchy="false">)</mo></mstyle></mrow><annotation encoding="application/x-tex">{\displaystyle x=C(t)}</annotation></semantics></math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/86528408d214c320fa5c44cd41639763a8ba52f6" class="mwe-math-fallback-image-inline" aria-hidden="true" style="vertical-align: -0.838ex; width:8.843ex; height:2.843ex;" alt="{\displaystyle x=C(t)}"></span></li>
<li><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 y=S(t)}"><semantics><mrow class="MJX-TeXAtom-ORD"><mstyle displaystyle="true" scriptlevel="0"><mi>y</mi><mo>=</mo><mi>S</mi><mo stretchy="false">(</mo><mi>t</mi><mo stretchy="false">)</mo></mstyle></mrow><annotation encoding="application/x-tex">{\displaystyle y=S(t)}</annotation></semantics></math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/8be5a48863b6470eefa32bdec3dd8ae562fff019" class="mwe-math-fallback-image-inline" aria-hidden="true" style="vertical-align: -0.838ex; width:8.402ex; height:2.843ex;" alt="{\displaystyle y=S(t)}"></span></li></ul>
<a href="//commons.wikimedia.org/wiki/User:Geek3" title="User:Geek3">Geek3</a>
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