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If A , B , C are angles in a triangle ,...

If `A , B , C ` are angles in a triangle , then prove that ` sin A + sin B + sin C =4 cos. (A)/(2) cos . (B)/(2) cos .(C)/(2)`

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The correct Answer is:
`=4 cos. (A)/(2) cos. (B)/(2) cos. (C)/(2)=R.H.S`
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