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If A+B+C =pi, then cos ^(2) A+ cos ^(...

If `A+B+C =pi,` then
`cos ^(2) A+ cos ^(2)B + cos^(2) C` is equal to

A

`1-4 sin A cos B sin C`

B

`1-2 cos A cos B cos C`

C

`1-2 sin A sin B cos C`

D

`1-4 sin A sin B cos C`

Text Solution

Verified by Experts

The correct Answer is:
C
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