sin(a - b) = sin(a)cos(b) - cos(a)sin(b) cos(a) = V(1 - sin^2(a)) = V(1 - 0.36) = 0.8 sin(b) = V(1 - cos^2(b)) = V(1 - 0.64) = 0.6 sin(a - b) = 0.6*0.8 - 0.8*0.6 = 0