2. Find the change-of-basis matrices PC-B and PB-c for the bases B = {1, cos 2x, sin 2x} and C={cos² x, sin² x, sin x cos x) of the vector space V = span(1, cos 2x, sin 2x). Then find the coordinate vectors [f(x)] and [f(x)]c of f(x) = 9 cos2 x + 24 sin x cos x + 16 sin² x relative to B and to C, respectively.