cos(252) = 0.2588cos(108) = 0.3090sin(252) = -0.9659sin(108) = 0.9511
Therefore, Cos252 cos108 -sin252 sin108 = (0.2588)(0.3090) - (-0.9659)(0.9511) = 0.0801 + 0.9189 = 0.9990
cos(252) = 0.2588
cos(108) = 0.3090
sin(252) = -0.9659
sin(108) = 0.9511
Therefore, Cos252 cos108 -sin252 sin108 = (0.2588)(0.3090) - (-0.9659)(0.9511) = 0.0801 + 0.9189 = 0.9990