If `sin A + sinB = I, cos A-cos B = m,` then `cos(A-B) =`

If sin A + sin B = I, cos A-cos B = m then cos (AB) =

If sinA+sinB=l and cosA-cosA-cosB=m , then cos(A-B)=

If sin A+sin B=a and cos A+cos B=b then cos (A+B)=

If sinA+sinB=a and cosA+cosB=b,then cos(A+B)

If sinA+sinB=a and cosA+cosB=b,then cos(A+B)

If sin (A-B)=sin A cos B-cos A sin B and cos (A - B) = cos A cos B + sin A sin B . find the values of sin 15^@ and cos 15^@.

In sinA=sinB and cos A=cos B , then prove that sin(A-B)/(2)=0

In sinA=sinB and cos A=cos B , then prove that sin((A-B)/2)=0