Find functions f$($x$)$

and g$($x$)$

so that h$($x$)=3$x$+15$

can be expressed as h$($x$)=$f$($g$($x$))$

$.$

Pick f

and g

such that f$($x$)!=$x

and g$($x$)!=$x

$.$

Enter your functions as a list $[$f$($x$),$g$($x$)]$

$.$