Given $f(x)=3 x^{2}-x$ And $g(x)=x^{3}+5 x^{2}-4$ , Find $\frac{d}{d x}[g(x)-3 f(x)]$

Essay

Given $f(x)=3 x^{2}-x$
and $g(x)=x^{3}+5 x^{2}-4$
, find $\frac{d}{d x}[g(x)-3 f(x)]$
.