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

The value of `cos""(pi)/(11)+cos""(3pi)/(11)+cos""(5pi)/(11)+cos""(7pi)/(11)+cos""(9pi)/(11),` is

A

0

B

`-1//2`

C

`1//2`

D

none of these

Text Solution

Verified by Experts

The correct Answer is:
C
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ML KHANNA-TRIGONOMETRY RATIOS AND IDENTITIES-PROBLEM SET (4) ( MULTIPLE CHOICE QUESTIONS)
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