Mathematics · 2025
JEE Main · 24 January 2025, Shift 2 · Q9
Suppose A and B are the coefficients of 30^th and 12^th terms respectively in the binomial expansion of (1+x)^2 n -1. If 2 A =5 B, then n is equal to:
Suppose A and B are the coefficients of $\displaystyle 30^{\text {th }}$ and $\displaystyle 12^{\text {th }}$ terms respectively in the binomial expansion of $\displaystyle (1+x)^{2 \mathrm{n}-1}$. If $\displaystyle 2 \mathrm{~A}=5 \mathrm{~B}$, then n is equal to :
Official answer
From NTA’s final answer key for this paper.
(4)
$\displaystyle 21$
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JEE Main 2025 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.