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If alpha+beta+gamma=2 theta,then cos the...

If `alpha+beta+gamma=2 theta`,then `cos theta + cos(theta - alpha) + cos(theta - beta) + cos(theta - gamma)` =

A

`4"sin" (alpha)/(2)."cos"(beta)/(2)."sin "(gamma)/(2)`

B

`4"cos "(alpha)/(2)."cos"(beta)/(2)."cos"(gamma)/(2)`

C

`4"sin "(alpha)/(2)."sin"(beta)/(2)."sin"(gamma)/(2)`

D

`4 sin alpha.sin beta. sin gamma`

Text Solution

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The correct Answer is:
B
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