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underset(r=1)overset(n-1)(sum)cos^(2)""(...

`underset(r=1)overset(n-1)(sum)cos^(2)""(rpi)/(n)` is equal to

A

`n/2-1`

B

`n/2-1/2`

C

`n/2`

D

None of these.

Text Solution

Verified by Experts

The correct Answer is:
A
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