Mathematics · 2015
JEE Main · 10 April 2015, Shift 1 · Q68
If the coefficients of the three successive terms in the binomial expansion of (1+x)^n are in the ratio 1: 7: 42, then the first of these terms in…
If the coefficients of the three successive terms in the binomial expansion of $\displaystyle (1+x)^{\mathrm{n}}$ are in the ratio $\displaystyle 1$ : $\displaystyle 7$ : $\displaystyle 42$, then the first of these terms in the expansion is :
Official answer
(2)
$\displaystyle 7^{\text {th }}$
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JEE Main 2015 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.