Q16 of 168 Page 205

Prove that the function f given by f (x) = log sin x is strictly increasing on and strictly decreasing on .

It is given that f (x) = log sin x


In interval, f’(x) = cot x >0


Therefore, f is strictly increasing in.


In interval, f’(x) = cot x < 0


Therefore, f is strictly decreasing in.


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