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If S=cos^2(pi/n)+cos^2((2pi)/n)+....+cos...

If `S=cos^2(pi/n)+cos^2((2pi)/n)+....+cos^2(((n-1)pi)/n),` then S equals

A

`(n)/(2(n+1))`

B

`(1)/(2(n-1))`

C

`(1)/(2)(n-2)`

D

`n/2`

Text Solution

Verified by Experts

The correct Answer is:
C
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