Mathematics · 2021
JEE Main · 16 March 2021, Shift 2 · Q64
Let f be a real valued function, defined on R -{-1,1} and given by f(x)=3 log_e|(x-1)/(x+1)|-2/(x-1). Then in which of the following intervals,…
Let $\displaystyle f$ be a real valued function, defined on $\displaystyle \mathbf{R}-\{-1,1\}$ and given by
$$f(x)=3 \log _e\left|\frac{x-1}{x+1}\right|-\frac{2}{x-1} .
$$
Then in which of the following intervals, function $\displaystyle f(x)$ is increasing ?
Official answer
(2)
$\displaystyle (-\infty,-1) \cup\left(\left[\frac{1}{2}, \infty\right)-\{1\}\right)$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.