Obtain an expression for the signal in figure, for the signal $${v_3}(t)$$ in Fig for $${v_1}(t) = 100\cos (2000\pi t) + 4\sin (200\pi t)$$. Assume that $${v_2}(t)$$=$${v_1}(t)$$+0.1 $$v_1^2(t)$$ and that the BPF is an ideal unity gain filter with pass band from 800 Hz to 1200 Hz.