the step i dont understand about the proof in this page http://en.wikipedia.org/wiki/Mean_value_theorem is the last one, where they assume that the x at which f'(x) is equal to the secant slope is the same x at which g'(x) = 0. can someone explain to me why this is so in a formal way?(adsbygoogle = window.adsbygoogle || []).push({});

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# Homework Help: Proof of the mean value theorem

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