JEE Main 12 Jan 2019 Morning Question 29
Question: Let 5 be the set of all points in $ (-\pi ,\pi ) $ at which the function, $ f(x)=\min {\sin x,\cos x} $ is not differentiable. Then S is a subset of which of the following? [JEE Main Online Paper Held On 12-Jan-2019 Morning]
Options:
A) $ { -\frac{\pi }{4},0,\frac{\pi }{4} } $
B) $ { -\frac{3\pi }{4},-\frac{\pi }{4},\frac{3\pi }{4},\frac{\pi }{4} } $
C) $ { -\frac{3\pi }{4},-\frac{\pi }{2},\frac{\pi }{2},\frac{3\pi }{4} } $
D) $ { -\frac{\pi }{2},-\frac{\pi }{4},\frac{\pi }{4},\frac{\pi }{2} } $
Show Answer
Answer:
Correct Answer: B
Solution:
- Here, $ y=\min [\sin x,\cos ,x] $ is not differentiable at $ { -\frac{3\pi }{4},\frac{\pi }{4} }. $
