What is the What is the fundamental frequency and fundamental period of the signal ( ) = 3 + sin 6 2 cos 6 + sin 9 cos 12 x(t)=3+sin6t2cos6t+sin9tcos12t Express it in complex Fourier series and plot the magnitudes and phases of its frequency components.fundamental frequency and fundamental period of the signal ? ( ? ) = 3 sin 6 ? 2 cos 6 ? ? sin 9 ? cos 12 ? x(t)=3 sin6t2cos6t sin9tcos12t Express it in complex Fourier series and plot the magnitudes and phases of its frequency components