$
\eqalign{
& f(x) = - 3e^{x + 6} + x \cr
& f'(x) = - 3e^{x + 6} \cdot 1 + 1 = - 3e^{x + 6} + 1 \cr
& \cr
& g(x) = \frac{x}
{{e^{x} }} \cr
& g'(x) = \frac{{1 \cdot e^{x} - x \cdot e^{x} }}
{{\left( {e^{x} } \right)² }} = \frac{{1 - x}}
{{e^{x} }} \cr
& \cr
& h(x) = xe^{x} + s \cr
& h'(x) = 1 \cdot e^{x} + x \cdot e^{x} = \left( {1 + x} \right)e^{x} \cr}
$