Plot of a <a href="https://en.wikipedia.org/wiki/Chebyshev_polynomials" class="extiw" title="en:Chebyshev polynomials">Chebyshev polynomial</a> of the first kind T<sub>30</sub> in the interval [-1.05, 1.05]:
<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 y(x)=T_{30}(x)}"><semantics><mrow class="MJX-TeXAtom-ORD"><mstyle displaystyle="true" scriptlevel="0"><mi>y</mi><mo stretchy="false">(</mo><mi>x</mi><mo stretchy="false">)</mo><mo>=</mo><msub><mi>T</mi><mrow class="MJX-TeXAtom-ORD"><mn>30</mn></mrow></msub><mo stretchy="false">(</mo><mi>x</mi><mo stretchy="false">)</mo></mstyle></mrow><annotation encoding="application/x-tex">{\displaystyle y(x)=T_{30}(x)}</annotation></semantics></math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/9756cf159e1b43443c9267874444ac792b47d957" class="mwe-math-fallback-image-inline" aria-hidden="true" style="vertical-align: -0.838ex; width:13.766ex; height:2.843ex;" alt="{\displaystyle y(x)=T_{30}(x)}"></span></li></ul>
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