(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Show that the rate of change of the area of a circle with respect to its radius is the same as the circumference of the circle. Can you suggest why?

2. Relevant equations

A = [tex]\pi[/tex]r[tex]^{2}[/tex] = f(r)

L = 2[tex]\pi[/tex]r = g(r)

3. The attempt at a solution

I have showed that the derivative of f(r) is equal to g(r).

But I have no idea why the area and the circumference of the circle are related in such a way. Any suggestions greatly appreciated.

Thank you.

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# Derivative of the Area of a Circle

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