Question $6$: $(2$ marks$)$

Determine the output ${?}^y[n]$ of the discrete$-$time system whose input and impulse response are given by $x[n]=(4{)}^{\text{'}}u[n-2]$ and $h[n]=(2{)}^{\text{'}}u[n],$ respectively. Use direct expression.

Hint: ${\displaystyle \underset{=m}{\overset{n}{}}}{r}^k=\frac{r^{n+1}-r^m}{r-1},r1.$