If A + B + C = `180^(@)`, prove that
sin A + sin B + sin C = 4 cos `(A)/(2) cos"" (B)/(2) cos"" (C )/(2)`

If A + B + C = 180^(@) , prove that cos A + cos B - cos C = -1 + 4 cos (A)/(2) cos"" (B)/(2) sin"" (C )/(2)

sin A + sin B + sin C = 4cos ((A) / (2)) cos ((B) / (2)) cos ((C) / (2))

If A + B + C = (pi)/(2) , prove that sin 2A + sin 2B + sin 2C = 4 cos A cos B cos C

If A + B + C =pi , prove that : . sin A + sin B+sinC = 4 cos frac (A)(2) cos frac (B)(2) cos frac (C)(2) .

If A + B + C = 180^(@) , prove that sin^(2)A + sin^(2)B + sin^(2) C = 2 + 2 cos A cos B cos C

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)

If A + B + C =180^@ , prove that : sin^2 A+ sin^2 B+sin^2 C=2 (1+cos A cos B cos C) .

Theorem 4:sin A+sin B+sin C=4(cos A)/(2)(cos B)/(2)(cos C)/(2)

If A + B + C= pi , prove that sin 2A + sin 2B -sin 2C =4cos A cos B sin C

If A + B + C =180^@ , prove that : sin^2 A- sin^2 B+ sin^2 C=2 sin A cos B sinC .