Find the value of cos""(pi)/(11)+cos""(3...

Find the value of `cos""(pi)/(11)+cos""(3pi)/(11)+cos""(5pi)/(11)+cos""(7pi)/(11)+cos""(9pi)/(11)`.

A

0

B

`-1//2`

C

`1//2`

D

1

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The correct Answer is:

C

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