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JEE MATHEMATICS MCQ: PERMUTATIONS

1 Easy

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The value of

{\;^n}{P_r}

is equal to

View answer and explanation

Correct option: A

{\;^{n - 1}}{P_r} + r.{\;^{n - 1}}{P_{r - 1}}

Option A,

{\;^{n - 1}}{P_r} + r.{\;^{n - 1}}{P_{r - 1}}

, is correct because it can be algebraically simplified to equal

{\;^n}{P_r}

using the formula for permutations.

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