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Question
Which of the following functions is decreasing on `(0, pi/2)`?
Options
sin2x
tanx
cosx
cos 3x
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Solution
cosx
Explanation:
Here, Let f x) = cos x
So, f'(x) = – sin x
f'(x) < 0 in `(0, pi/2)`
So f(x) = cos x is decreasing in `(0, pi/2)`
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