Symmetric and asymmetric periodic waveforms, with one half of a cycle ghosted and flipped to show the difference.  The red is symmetric and green is asymmetric. <br><p>Red is:
</p>
<dl><dd><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 f(t)=\cos(t)+\cos(3t+1)+0.2\cdot \cos(7t+5)}"><semantics><mrow class="MJX-TeXAtom-ORD"><mstyle displaystyle="true" scriptlevel="0"><mi>f</mi><mo stretchy="false">(</mo><mi>t</mi><mo stretchy="false">)</mo><mo>=</mo><mi>cos</mi><mo>⁡<!-- ⁡ --></mo><mo stretchy="false">(</mo><mi>t</mi><mo stretchy="false">)</mo><mo>+</mo><mi>cos</mi><mo>⁡<!-- ⁡ --></mo><mo stretchy="false">(</mo><mn>3</mn><mi>t</mi><mo>+</mo><mn>1</mn><mo stretchy="false">)</mo><mo>+</mo><mn>0.2</mn><mo>⋅<!-- ⋅ --></mo><mi>cos</mi><mo>⁡<!-- ⁡ --></mo><mo stretchy="false">(</mo><mn>7</mn><mi>t</mi><mo>+</mo><mn>5</mn><mo stretchy="false">)</mo></mstyle></mrow><annotation encoding="application/x-tex">{\displaystyle f(t)=\cos(t)+\cos(3t+1)+0.2\cdot \cos(7t+5)}</annotation></semantics></math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/a15a2309b4a3d3701c8794757589563c7c56991c" class="mwe-math-fallback-image-inline" aria-hidden="true" style="vertical-align: -0.838ex; width:44.968ex; height:2.843ex;" alt="{\displaystyle f(t)=\cos(t)+\cos(3t+1)+0.2\cdot \cos(7t+5)}"></span></dd></dl><p>Green is:
</p>
<dl><dd><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 f(t)=\cos(t)+\cos(2t+1)+0.2\cdot \cos(6t+5)}"><semantics><mrow class="MJX-TeXAtom-ORD"><mstyle displaystyle="true" scriptlevel="0"><mi>f</mi><mo stretchy="false">(</mo><mi>t</mi><mo stretchy="false">)</mo><mo>=</mo><mi>cos</mi><mo>⁡<!-- ⁡ --></mo><mo stretchy="false">(</mo><mi>t</mi><mo stretchy="false">)</mo><mo>+</mo><mi>cos</mi><mo>⁡<!-- ⁡ --></mo><mo stretchy="false">(</mo><mn>2</mn><mi>t</mi><mo>+</mo><mn>1</mn><mo stretchy="false">)</mo><mo>+</mo><mn>0.2</mn><mo>⋅<!-- ⋅ --></mo><mi>cos</mi><mo>⁡<!-- ⁡ --></mo><mo stretchy="false">(</mo><mn>6</mn><mi>t</mi><mo>+</mo><mn>5</mn><mo stretchy="false">)</mo></mstyle></mrow><annotation encoding="application/x-tex">{\displaystyle f(t)=\cos(t)+\cos(2t+1)+0.2\cdot \cos(6t+5)}</annotation></semantics></math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/fbf647484bf6367124b58a8cc697a7b67265c48a" class="mwe-math-fallback-image-inline" aria-hidden="true" style="vertical-align: -0.838ex; width:44.968ex; height:2.843ex;" alt="{\displaystyle f(t)=\cos(t)+\cos(2t+1)+0.2\cdot \cos(6t+5)}"></span></dd></dl>
Created by <a href="//commons.wikimedia.org/wiki/User:Omegatron" title="User:Omegatron">User:Omegatron</a> using <a href="https://en.wikipedia.org/wiki/GraphCalc" class="extiw" title="w:GraphCalc">GraphCalc</a>
CC BY-SA 3.0
<span class="int-own-work" lang="en">Own work</span>