Mathematics · 2020
JEE Main · 2 September 2020, Shift 2 · Q71
For a positive integer n,(1+1/x)^n is expanded in increasing powers of x. If three consecutive coefficients in this expansion are in the ratio, 2: 5:…
For a positive integer $\displaystyle \mathrm{n},\left(1+\frac{1}{x}\right)^{\mathrm{n}}$ is expanded in increasing powers of $\displaystyle x$. If three consecutive coefficients in this expansion are in the ratio, $\displaystyle 2$ : $\displaystyle 5$ : $\displaystyle 12$, then n is equal to \_\_\_\_.
Official answer
118
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JEE Main 2020 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.