2.1 Sketch the single-sided and double-sided amplitude and phase spectra of the following signals: (a) x₁(t) = 10 cos(4лt +л/8)+6 sin(8лt +3л/4) (b) x(t) = 8 cos(2лt+л/3)+4 cos(блt +л/4) (c) x(t) = 2 sin(4лt +л/8) + 12 sin(10лt) (d) x(t) = 2 cos(7лt +л/4)+3 sin(18лt+л/2) (e) x(t) = 5 sin(2лt) + 4 cos(5лt +л/4) (f) x(t) = 3 cos(4лt+л/8)+4 sin(10лt +л/6)