Skip to main content
Back to DIFFERENTIATION

JEE MATHEMATICS MCQ: DIFFERENTIATION

1 Medium
1 of 1
Application +4 | -1
If f(x)=cos⁡xcos⁡2xcos⁡22xcos⁡23x……f(x)=\cos x \cos 2 x \cos 2^2 x \cos 2^3 x \ldots \ldots cos⁡2n−1x\cos 2^{n-1} x and n>1n>1, then f′(π2)f^{\prime}\left(\frac{\pi}{2}\right) is
View answer and explanation
Correct option: A
1
Option A (1) is correct because by using the identity sin⁡(2x)=2sin⁡(x)cos⁡(x)\sin(2x) = 2\sin(x)\cos(x) repeatedly, we can simplify f(x)f(x) to sin⁡(2nx)2nsin⁡(x)\frac{{\sin(2^n x)}}{{2^n \sin(x)}}, then differentiate and evaluate at x=π2x = \frac{{\pi}}{{2}}.

More Questions from DIFFERENTIATION

Practice All Chapter MCQs →
Type at least 2 characters or jump directly:
🔓

Save your learning progress

Sign in with a free account to save your practice answers and quiz results, then return to them when you revise.