`4Rcos(A/2)cos(B/2)cos(C/2)=`

If A+B+C=180 , prove that: sinA+sinB+sinC=4cos(A/2)cos(B/2)cos(C/2)

If A+B-C=3pi, t h e n sin A+ sin B-sin C is equal to- a.4sin(A/2)sin(B/2)cos(C/2) b. -4sin(A/2)sin(B/2)cos(C/2) c. 4cos(A/2)cos(B/2)cos(C/2) d. -4cos(A/2)cos(B/2)cos(C/2)

If A+B-C=3pi,\ t h e n\ sin A+ sin B-sin C is equal to- a. 4sin(A/2)sin(B/2)cos(C/2) b. -4sin(A/2)sin(B/2)cos(C/2) c. \ 4cos(A/2)cos(B/2)cos(C/2) d. -4cos(A/2)cos(B/2)cos(C/2)

If A+B+C=pi , prove that : sinA+sinB+sinC= 4cos( A/2 )cos( B/2) cos(C/2)

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

If A+B+C = 2S , then P.T cos(S-A)+cos(S-B)+cos(S-C)+cosS=4cos.(A)/(2)cos.(B)/(2)cos.(C)/(2)

In DeltaABC,4Rrcos""A/2cos""B/2cos""C/2=

If A+B+C=180^(@) then cos2A+cos2B+cos2C=1-4cos A cos B cos C 2.If A+B+C=0 then cos A+cos B+cos C=-1+4(cos A)/(2)(cos B)/(2)(cos C)/(2)

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

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))