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If f(x) = cos(ln(x5)), find f ′(1).

User Max Wallace
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2 Answers

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f(x)=\cos[\ln(x^5)]\implies \stackrel{chain~rule}{\cfrac{df}{dx}=-\sin[\ln(x^5)]\cdot \cfrac{1}{x^5}\cdot 5x^4} \\\\\\ \left. \cfrac{df}{dx}=-\cfrac{5\sin[\ln(x^5)]}{x} \right|_(x=1)\implies -\cfrac{5\sin[\ln(1^5)]}{1}\implies -\cfrac{5\sin(0)}{1}\implies 0

User Notrace
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Answer:

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Explanation:

If f(x) = cos(ln(x5)), find f ′(1).-example-1
User Afrim
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