Mathematics · 2021
JEE Main · 25 February 2021, Shift 1 · Q65
If Rolle's theorem holds for the function f(x)=x^3- a x^2+ b x-4, x ∈[1,2] with f^′(4/3)=0, then ordered pair ( a, b ) is equal to:
If Rolle's theorem holds for the function $\displaystyle f(x)=x^3-\mathrm{a} x^2+\mathrm{b} x-4, x \in[1,2]$ with $\displaystyle f^{\prime}\left(\frac{4}{3}\right)=0$, then ordered pair $\displaystyle (\mathrm{a}, \mathrm{b})$ is equal to :
Official answer
(1)
$\displaystyle (5,8)$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.