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sin "" (2pi)/(7) + sin "" (4pi)/(7) + si...

`sin "" (2pi)/(7) + sin "" (4pi)/(7) + sin "" (8pi)/(7) =`

A

`sqrt7//2`

B

`7//2`

C

`-sqrt7//2`

D

`-7//2`

Text Solution

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The correct Answer is:
A
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