SOLUTION: Use logarithmic differentiation to find the derivative of the function. y = (ln x)^cos 4x

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Question 959768: Use logarithmic differentiation to find the derivative of the function.

y = (ln x)^cos 4x
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
ln%28y%29+=+ln%28%28ln+x%29%5E%28cos%284x%29%29%29
ln%28y%29+=+cos%284x%29%2Aln%28%28ln%28x%29%29%29%29
So then differentiating,

dy%2Fdx=y%28cos%284x%29%2F%28x%2Aln%28x%29%29-4sin%284x%29%2Aln%28ln%28x%29%29%29%29