Mathematics · 2025
JEE Main · 22 January 2025, Shift 2 · Q21
If Σ_r =1^30 (r^2(^30 C_r )^2)/(^30 C_r -1)=α × 2^29, then α is equal to ____.
If $\displaystyle \sum_{\mathrm{r}=1}^{30} \frac{\mathrm{r}^2\left({ }^{30} \mathrm{C}_{\mathrm{r}}\right)^2}{{ }^{30} \mathrm{C}_{\mathrm{r}-1}}=\alpha \times 2^{29}$, then $\displaystyle \alpha$ is equal to $\displaystyle \_\_\_\_$.
Official answer
From NTA’s final answer key for this paper.
465
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JEE Main 2025 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.