Which expression is equal to sin(A+B)+sin(A−B)\sin(A+B) + \sin(A-B)sin(A+B)+sin(A−B)?
2sin(A)cos(B)2\sin(A)\cos(B)2sin(A)cos(B)
2cos(A)sin(B)2\cos(A)\sin(B)2cos(A)sin(B)
2sin(A)sin(B)2\sin(A)\sin(B)2sin(A)sin(B)
2cos(A)cos(B)2\cos(A)\cos(B)2cos(A)cos(B)