sum(r=0)^n(-2)^r*(nCr)/((r+2)Cr) is equa...

`sum_(r=0)^n(-2)^r*(nC_r)/((r+2)C_r)` is equal to

A

`(1)/(n+1)`, n is odd

B

`(1)/(n+2)`, n is even

C

`(1)/(n+1)`, n is even

D

None of these

Verified by Experts

The correct Answer is:

C

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