2. Let f(x) = cos x + sin 2x with its fundamental period being 2n and f (x) = do + En=llan cos(nx) + bn sin(nx)]. - Compute a, and b2. Hint: use cos' x = (1 + cos 2x) and sin 2x = NIP (1 - NI cos 4x) - Show that all other coefficients are zero. Hint: use orthogonality