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If a(r) is the coefficient of x^(r) in t...

If `a_(r)` is the coefficient of `x^(r)` in the expansion of
`( 1 + x + x^(2))^(n)`, then `a_(1) - 2a_(2) + 3a_(3) ……… -2n a_(2n) = `

A

0

B

n

C

`-n`

D

2n

Text Solution

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The correct Answer is:
C
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