Q$3.$ A system is described by the difference equation

$y[n]=x[n]-2x[n-2]$

a$)$ Compute $H(e^j)=\frac{Y(e^j)}{x(e^j)}$ of the system.

b$)$ Determine the output of the system for the following input:

$x[n]=3+6cos(\frac{}{3}n)+5sin(\frac{2}{5}n+\frac{}{2}),-$