Mathematics · 2023
JEE Main · 31 January 2023, Shift 2 · Q85
If ^2 n+1 P_n-1:^2 n-1 P_n=11: 21, then n^2+n+15 is equal to:
If $\displaystyle { }^{2 n+1} \mathrm{P}_{n-1}:{ }^{2 n-1} \mathrm{P}_n=11: 21$, then $\displaystyle n^2+n+15$ is equal to :
Official answer
From NTA’s final answer key for this paper.
45
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JEE Main 2023 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.