If A,B,C are angles in a triangle , then prove that `cosA+cosB+cosC=1+4sin. (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 are the angles of a triangle then prove that cosA+cosB-cosC=-1+4cos(A/2)cos(B/2)sin(C/2)

If A,B,C are the angles of a triangle then prove that cosA+cosB-cosC=-1+4cos(A/2)cos(B/2)sin(C/2)

If A, B, C are the angles in a triangle then prove that sin .(A)/(2)+ sin . (B)/(2)+ sin .(C)/(2) =1 +4 sin((pi-A)/(4)) sin ((pi-B)/(4)) sin((pi-C)/(4))

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 are angles in the triangle, then prove that cosA+cosB-cosC=-1+4cos""A/2.cos""B/2.sin""C/2

If A,B, C are angles in a triangle, then prove that: sin^(2) A + sin^(2) B - sin^(2) C =2 sin A sin B cos C

Prove that cosA -cosB -cosC =1-4sin(A/2)cos(B/2)cos(C/2) ,if A+B+C= pi

If A, B, C are angles of a triangle , prove that sin 2A+sin 2B-sin 2C=4cos Acos B sin C

If A, B, C are the angles of a triangle, prove that sin2A+sin2B+sin2C=4sinAsinBsinC