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If A+B +C = 270^@, then cos 2A + cos 2B ...

If `A+B +C = 270^@`, then cos 2A + cos 2B +cos 2C +4sin A sin B sin C=

A

3

B

2

C

1

D

`-1`

Text Solution

Verified by Experts

The correct Answer is:
C
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