If `A+B+C=pi/2` then `sumcos(B+C)/(cosBcosC)=`

If A+B+C=(pi)/(2) then sum(cos(B+C))/(cos B cos C)=

If A+B+C=(pi)/(2) then cos(A+C)=

If A+B+C=pi then sin(A+B)+cos(A+C)=

If A+B+C=(3pi)/(2) , then cos2A+cos2B+cos2C=?

If A+B+C = (3pi)/(2),then cos2A+cos2B+cos2C=

If A+B+C=pi then cos((B)/(2))+cos((C)/(2)) equals

If A+B+C=pi then prove cos( (A)/2) cos( (B-C)/2) + cos( B/2) cos((C-A)/2) + cos( C/2) cos( (A-B)/2) = sinA +sinB+sinC

If A+B+C=3pi/2 . Then cos 2A +cos 2B+cos2C is equal to

If A+B+C=pi , then cos^(2)A+cos^(2)B+cos^(2)C is equal to