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Prove that: sin, (2pi)/7 + sin, (4pi)/7 ...

Prove that: `sin, (2pi)/7 + sin, (4pi)/7 +sin, (8pi)/7 = sqrt(7)/2`

A

1

B

`sqrt(2)`

C

`2`

D

`sqrt(3)`

Text Solution

Verified by Experts

The correct Answer is:
D
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