Mathematics · 2021
JEE Main · 25 July 2021, Shift 2 · Q63
If ^n P_r=^n P_r+1 and ^n C_r=^n C_r-1, then the value of r is equal to:
If $\displaystyle { }^n P_r={ }^n P_{r+1}$ and $\displaystyle { }^n C_r={ }^n C_{r-1}$, then the value of $\displaystyle r$ is equal to :
Official answer
(2)
$\displaystyle 2$
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JEE Main 2021 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.