If `A+B+C=pi`, then `sin2A+sin2B-sin2C` is equal to

If A+B-C=3 pi, then sin A+sin B-sin C is equal to -

If A+B+C=pi, the value of sin2A+sin2B+sin2C=k sin A sin B sin C then value of k is

if A+B+C=180^(@), then what is sin2A-sin2B-sin2C equal to?

If (tan(A+B+C))/(tan(A-B+C))=(tanC)/(tanB) then sin2A+sin2B+sin2C is equal to_______

If : A+B+C=pi, "then" : sin 2A + sin 2 B - sin 2 C= A) 4 sin A * cos B * cos C B) 4 sin B * sin C * cos A C) 4 sin C * cos A * cos B D) 4 sin A * sin B * sin C