" In triangle "ABC," prove that "cos(A)/(2)+cos(B)/(2)+cos(C)/(2)=4cos(pi-A)/(4)cos(pi-B)/(4)cos(pi-C)/(4)

In triangle ABC,prove that cos((A)/(2))+cos((B)/(2))+cos((C)/(2))=4(cos(pi-A))/(4)(cos(pi-B))/(4)(cos(pi-C))/(4)

In triangle ABC, prove that cos .(A)/(2)+cos.(B)/(2)+cos. (C)/(2) =4 cos .(pi-A)/(4)cos. (pi-B)/(4) cos.(pi-C)/(4)

In triangle ABC, prove that cos(A/2)+cos(B/2)+cos(C/2)=4cos(pi-A)/4cos(pi-B)/4cos(pi-C)/4

In Delta ABC , prove that cos. (A)/(2)+cos. (B)/(2) - cos .(C)/(2)=4cos .(pi+A)/(4) cos. (pi+B)/(4) cos. (pi-C)/(4)

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

In triangle ABC , prove that sin .(A)/(2)+ sin. (B)/(2) -sin. (C)/(2)=-1+4 cos.(pi-A)/(4)cos. (pi-B)/(4)sin. (pi-C)/(4)

If A +B+C = 180^circ , prove that cos A/2+ cos B/2 +cos C/2 = 4cos (pi-A)/4 * cos(pi-B)/4 cos(pi-C)/4

In any triangle ABC, prove that : cos frac (A)(2) +cos frac (B)(2)+cos frac (C)(2)= 4 cos frac (pi-A)(4) cos frac (pi-B)(4) cos frac (pi-C)(4) .

prove that cos2(pi)/(7)+cos4(pi)/(7)+cos6(pi)/(7)=-(1)/(2)

If A+B+C=180^(@) then prove the following: "cos"A/2+"cos"B/2+"cos"C/2 =4cos((pi-A)/4)cos((pi-B)/4)cos((pi-C)/4)