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

If `S=cos^2pi/2+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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ARIHANT MATHS-TRIGONOMETRIC FUNCTIONS AND IDENTITIES-Exercise (Questions Asked In Previous 13 Years Exam)
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