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If A+B+C=pi, prove that sin 2A+sin 2B+si...

If `A+B+C=pi`, prove that `sin 2A+sin 2B+sin 2C=4 sinA sin B sinC.`

A

`4 sin A . sin B . sin C`

B

`4 cos A . cos B . cos C`

C

`2 sin A . sin B . sin C`

D

`8 sin A . sin B . sin C`

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