2. The sinusoidal signal x(t) = 3 cos(200t + π/6) is passed through a square-law device defined by the input-output relation y(t) = x²(t). Using the trigonometric identity cos² = (cos 20+ 1), show that the output y(t) consists of a dc component and a sinusoidal component. (a) Specify the dc component. (b) Specify the amplitude and fundamental frequen- cy of the sinusoidal component in the output y(t).