$9-)$ A mass$-$spring system subjected to an oscillating forcing function described by F$($t$)=2\mathrm{.}3$ cos $8\mathrm{.}5$t$.$ The effective mass and spring stiffness are $1\mathrm{.}5$ kg and $57$ N$/$m respectively. Determine the steady$-$state solution$\mathrm{.}9-)$ A mass$-$spring system subjected to an oscillating forcing function described by $F(t)=2\mathrm{.}3cos$

$8\mathrm{.}5$t$.$ The effective mass and spring stiffness are $1\mathrm{.}5kg$ and $57\frac{N}{m}$ respectively. Determine the

steady$-$state solution.