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If xn=cos(pi/2^n)+isin(pi/2^n), then x1 ...

If `x_n=cos(pi/2^n)+isin(pi/2^n)`, then x1 x2 x3......infinity

A

-1

B

1

C

`1//sqrt2`

D

`i//sqrt2`

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The correct Answer is:
A
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