Mathematics · 2023
JEE Main · 6 April 2023, Shift 2 · Q7
If the coefficients of x^7 in (a x^2+1/(2 b x))^11 and x^-7 in (a x-1/(3 b x^2))^11 are equal, then
If the coefficients of $\displaystyle x^7$ in $\displaystyle \left(a x^2+\frac{1}{2 b x}\right)^{11}$ and $\displaystyle x^{-7}$ in $\displaystyle \left(a x-\frac{1}{3 b x^2}\right)^{11}$ are equal, then
Official answer
From NTA’s final answer key for this paper.
(4)
$\displaystyle 729 a b=32$
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JEE Main 2023 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.