Illustration of Mamikon's Theorem 'The area of a tangent sweep is equal to the area of its tangent cluster, regardless of the shape of the original curve' in visual calculus.
<a href="//commons.wikimedia.org/wiki/User:Dmcq" title="User:Dmcq">Dmcq</a>
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<span class="int-own-work" lang="en">Own work</span>