cos A+cos B+cos C=1+4sin(A)/(2)sin(B)/(2)sin(C)/(2)

Theorem 3:cos A+cos B+cos C=1+4(sin A)/(2)(sin B)/(2)(sin C)/(2)

If A + B + C = pi , prove that cos A + cos B + cos C= 1 + 4 sin(A/2) sin(B/2) sin(C/2)

If A + B + C = pi then prove that cos A + cos B + cos C = 1 + 4 sin(A/2) .sin(B/2).sin(C/2)

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

If A + B + C =pi , prove that : cos A+cos B+cos C=1+ 4 sin frac (A)(2) sin frac (B)(2) sin frac (C)(2) .

If cos(A+B+C)=cos A cos B cos C , then (8sin(B+C)sin(C+A)sin(A+B))/(sin2A sin 2B sin 2C)=

If A+B+C=(3pi)/(2), prove that cos 2A+ cos 2B+ cos 2C=1-4 sin A sin B sin C .

If A+B+C=(pi)/(2) , then prove that cos 2A + cos 2B + cos 2C=1+4 sin A sin B sin C .

If A+B +C = 270^@ , then cos 2A + cos 2B +cos 2C +4sin A sin B sin C=

If A+B+C=(3 pi)/(2), then cos2A+cos2B+cos2C is equal to (A)1-4cos A cos B cos C(B)4sin A sin B sin C(C)1+42cos A cos B cos C(D)1-4sin A sin B sin C