Q$6-($a$)$ Let $x[n]$ be the discrete time sequence having fundamental period $N=4$ with

$\frac{1}{2}$

$x[n]=\{\begin{array}{ccc}1& if& n=0\\ -1& if& n=1\\ 0& if& n=2\\ 1& if& n=3\end{array}$

a$)$ Determine DTFS coefficients.

b$)$ Write Matlab code to determine $x[k]$