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

Find dy/dx of y=(cosx)^x

2. Relevant equations

d/dx of a^u=lna*a^u*u'

3. The attempt at a solution

I thougt I just had to follow the form shown above, and this is what I got.

y=(cosx)^x

dy/dx=ln(cosx)*(cosx)^x*1

dy/dx=ln(cosx)*(cosx)^x

However, the actual answer is (cosx)^x*(ln(cosx)-xtanx)

I don't understand where this comes from at all. Thanks for your input.

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Find dy/dx of y=(cosx)^x

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