In a triangle ABC,prove that sin3Asin(B-C)+sin3Bsin(C-A)+sin3Csin(A-B)=0

Dear student

Please approach using

( Sin A/ a) = ( sin B / b ) = ( sin C / c) = k

Expand sin 3A = 3ak - 4 ( ak)^3

If doubt still persists kindly revert for complete solution

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