Maths-

General

Easy

Question

# If ^{(m+n) }P_{2} = 56 and ^{m–n}P_{2} = 12 then (m, n) equals-

- (5, 1)
- (6, 2)
- (7, 3)
- (9, 6)

Hint:

## The correct answer is: (6, 2)

Similarly

Adding (1) and (2), we get

Substituting m= 6 in (2), we get

Thus, If and then (m, n) equals- (6,2)

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