JEE Main 2021 — Application Of Derivatives Question with Solution
From: JEE Main 2021 (Online) 17th March Evening Shift
Question
Consider the function f : R R defined by
. Then f is :
. Then f is :
Choose an option
Show full solutionCorrect option: A
Correct answer
Anot monotonic on (, 0) and (0, )
Step-by-step explanation
f(x) = \left\{ {\matrix{
{ - \left( {2 - \sin {1 \over x}} \right)x} & , & {x < 0} \cr
0 & , & {x = 0} \cr
{\left( {2 - \sin {1 \over x}} \right)x} & , & {x > 0} \cr
} } \right.
=
f'(x) is an oscillating function which is non-monotonic on (, 0) and (0, ).
=
f'(x) is an oscillating function which is non-monotonic on (, 0) and (0, ).
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