$\displaystyle f(x)= \frac{{x}^{3 }-{4x}^{2 }+3 }{x } $

$\displaystyle f'(x)=\f{3x}^{2 }-8x +{x}^{ -2} $

I'm kinda confused on what happens to the x in the denominator i don't know if i should add it or multiply the numerator by it so that is the answer i felt most comfortable