An LTI filter is described by the difference equation

y$[$n$]=3$x$[$n$]+2$x$[$n $1]+$ x$[$n $2]$

$($a$)$ Obtain an expression for the frequency response of this system.

$($b$)$ Determine the output when the input is x$[$n$]=1+2$ cos$(0\mathrm{.}5$n $+0\mathrm{.}1$ $)$ for

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