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The value of 2"cos"(pi)/(13)"cos"(9pi)/(...

The value of `2"cos"(pi)/(13)"cos"(9pi)/(13)+"cos"(3pi)/(13)+"cos"(5pi)/(13)` is

A

`-1`

B

0

C

1

D

None of these

Text Solution

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The correct Answer is:
B
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