If x(r)=cos. (pi)/(2^(r))+ isin. (pi)/(2...

If `x_(r)=cos. (pi)/(2^(r))+ isin. (pi)/(2^(r))`, then `x_(1)x_(2)x_(3)....oo=`

A

`1//2`

B

`-1`

C

0

D

1

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The correct Answer is:

B

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