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The value of cos(pi/19)+cos((3pi)/19)+co...

The value of `cos(pi/19)+cos((3pi)/19)+cos((5pi)/19)+`......`+cos((17pi)/19)` is (a)`1/2` (b)0 (c)1 (d)none

A

0

B

`1/2`

C

`-1/2`

D

none of these

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A
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MOTION-TRIGNOMETRIC RATIOS & IDENTITIES -Exercise 2(Level -I)
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