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If x +y+z = 180^@, then cos2x + cos2y-...

If `x +y+z = 180^@`, then `cos2x + cos2y-cos2z` is equal to

A

`4 sin x sin y sin z`

B

` 1-4 sin x sin y cos z`

C

`4 sin x sin y sin z-1`

D

`cos x cos y cos z`

Text Solution

Verified by Experts

The correct Answer is:
B
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