Mathematics · 2021
JEE Main · 17 March 2021, Shift 2 · Q69
Consider the function f: R → R defined by f(x)= {(2- sin (1/x))|x|, x ≠ 0; 0, x=0}. Then f is:
Consider the function $\displaystyle f: \mathbf{R} \rightarrow \mathbf{R}$ defined by $\displaystyle f(x)=\left\{\begin{array}{cc}\left(2-\sin \left(\frac{1}{x}\right)\right)|x|, & x \neq 0 \\ 0, & x=0\end{array}\right.$. Then $\displaystyle f$ is :
Official answer
(4)
not monotonic on $\displaystyle (-\infty, 0)$ and $\displaystyle (0, \infty)$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.