A,B,C are acute angles of triangle ABC,show that sin (B+C/2)=cos (A/2)

1.	A,B,C are acute angles of triangle ABC,show that sin (B+C/2)=cos (A/2)
Answer» In triangle ABC , A+B+C=180 (Asp)So, B+C=180- A Now, sin ( b+C/2)Sin(180-A/2)Sin (180/2-A/2)Sin ( 90- A/2 )Which is cosA/2=RHS

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