Mathematics · 2021
JEE Main · 16 March 2021, Shift 1 · Q70
The range of a ∈ R for which the function f(x)=(4 a -3)(x+ log_e 5)+2( a -7) cot (x/2) sin^2(x/2), x ≠ 2 n π, n ∈ N has critical points, is:
The range of $\displaystyle \mathrm{a} \in \mathbf{R}$ for which the function $\displaystyle f(x)=(4 \mathrm{a}-3)\left(x+\log _{\mathrm{e}} 5\right)+2(\mathrm{a}-7) \cot \left(\frac{x}{2}\right) \sin ^2\left(\frac{x}{2}\right), x \neq 2 \mathrm{n} \pi, \mathrm{n} \in \mathrm{N}$ has critical points, is :
Official answer
(3)
$\displaystyle \left[-\frac{4}{3}, 2\right]$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.