Mathematics · 2024
JEE Main · 1 February 2024, Shift 1 · Q7
If 5 f(x)+4 f(1/x)=x^2-2, ∀ x ≠ 0 and y=9 x^2 f(x), then y is strictly increasing in:
If $\displaystyle 5 f(x)+4 f\left(\frac{1}{x}\right)=x^2-2, \forall x \neq 0$ and $\displaystyle y=9 x^2 f(x)$, then $\displaystyle y$ is strictly increasing in:
Official answer
From NTA’s final answer key for this paper.
(3)
$\displaystyle \left(-\frac{1}{\sqrt{5}}, 0\right) \cup\left(\frac{1}{\sqrt{5}}, \infty\right)$
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JEE Main 2024 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.