Problem $4[10$ pts$]$ If input x$[$n$]=9+2$ cos $2$ n $+3$ cos$($n$),$ and x$[$n$]5$y$[$n$]+3$y$[$n $1]+$ y$[$n $2]=7$x$[$n$]+6$x$[$n $1]$ x$[$n $2]$ y$[$n$]$ a$.[5$ pts$]$ Compute the frequency response H$($e j$).$ b$.[5$ pts$]$ Compute the output y$[$n$].$