Mathematics · 2023
JEE Main · 25 January 2023, Shift 1 · Q64
If a_r is the coefficient of x^10-r in the Binomial expansion of (1+x)^10, then Σ_r=1^10 r^3(a_r/(a_r-1))^2 is equal to
If $\displaystyle a_r$ is the coefficient of $\displaystyle x^{10-r}$ in the Binomial expansion of $\displaystyle (1+x)^{10}$, then $\displaystyle \sum_{r=1}^{10} r^3\left(\frac{a_r}{a_{r-1}}\right)^2$ is equal to
Official answer
From NTA’s final answer key for this paper.
(4)
$\displaystyle 1210$
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JEE Main 2023 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.