Parallel curves of a sine wave, specifically <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=1.5\sin(x)}"><semantics><mrow class="MJX-TeXAtom-ORD"><mstyle displaystyle="true" scriptlevel="0"><mi>y</mi><mo>=</mo><mn>1.5</mn><mi>sin</mi><mo>⁡<!-- ⁡ --></mo><mo stretchy="false">(</mo><mi>x</mi><mo stretchy="false">)</mo></mstyle></mrow><annotation encoding="application/x-tex">{\displaystyle y=1.5\sin(x)}</annotation></semantics></math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/c8cb7f7fa56b6064965ffdd5a26c84328213a0bd" class="mwe-math-fallback-image-inline" aria-hidden="true" style="vertical-align: -0.838ex; width:13.607ex; height:2.843ex;" alt="{\displaystyle y=1.5\sin(x)}"></span>
<a href="//commons.wikimedia.org/wiki/User:Ag2gaeh" title="User:Ag2gaeh">Ag2gaeh</a>
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