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"cos"pi/7+"cos"(2pi)/7+"cos"(3pi)/7+"cos...

`"cos"pi/7+"cos"(2pi)/7+"cos"(3pi)/7+"cos"(4pi)/7+"cos"(5pi)/7+"cos"(6pi)/7 =`

A

0

B

`3/2`

C

`3/4`

D

1

Text Solution

Verified by Experts

The correct Answer is:
D
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