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If ( 1 + x - 2x^(2))^(20) = sum(r=0)^(4...

If ` ( 1 + x - 2x^(2))^(20) = sum_(r=0)^(40) a_(r) x^(r) ` , then find
the value of ` a_(1) + a_(3) + a_(5) + …+ a_(39)` .

A

`2^(20)(2^(20)+1)`

B

`2^(20)(2^(20)+1)`

C

`2^(39)-2^(19)`

D

`2^(39)+2^(19)`

Text Solution

Verified by Experts

The correct Answer is:
C
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