So I know that the derivative of the area of a circle is 2∏r or the circumference, and that the derivative of the area of a square is the perimeter or 2x. I don't get how these are the derivatives because there isn't a time involved. I thought that the derivative measured the rate of change and if so how do these derivatives without time measure this change?(adsbygoogle = window.adsbygoogle || []).push({});

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# The derivative without time.

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