" 2.If "A+B+C=180^(@)," then 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 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)

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)

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)

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

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