Mathematics · 2021
JEE Main · 25 July 2021, Shift 1 · Q67
Let f(x)=3 sin^4 x+10 sin^3 x+6 sin^2 x-3, x ∈[-(π)/6, (π)/2]. Then, f is:
Let $\displaystyle f(x)=3 \sin ^4 x+10 \sin ^3 x+6 \sin ^2 x-3, x \in\left[-\frac{\pi}{6}, \frac{\pi}{2}\right]$. Then, $\displaystyle f$ is :
Official answer
(4)
decreasing in $\displaystyle \left(-\frac{\pi}{6}, 0\right)$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.