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9. 10 Is the set {sin nx , cos mx} an orthogonal set with respect to the inner product on the set of all continuous real-valued functions given by (f, g) = S_fg dt ? Justify your answer. Note: 1 - cos(2x) 1 + cos(2x) sin x = cos x = - 2 sin A cos B = [sin (A - B) + sin(A + B)] NIANIPNIAN sin A sin B = [cos(A - B) - cos(A + B)] COS A Cos B = [cos(A - B) + cos(A + B)]