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JEE MATHEMATICS MCQ: PERMUTATIONS

1 Easy

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Application +4 | -1

If

{ }^{m+n} P_2=90

and

{ }^{m-n} P_2=30,

then

(m, n)

is given by

View answer and explanation

Correct option: D

(8,2)

Option D ((8,2)) is correct because it is derived by solving the permutation equations for m and n.

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