How do you differentiate f(x)=e^x/x-3x using the quotient rule?

$f ' \left(x\right) = \frac{\frac{d}{\mathrm{dx}} \left({e}^{x}\right) \cdot x - \frac{d}{\mathrm{dx}} \left(x\right) \cdot {e}^{x}}{x} ^ 2 - \frac{d}{\mathrm{dx}} \left(3 x\right)$
$= \frac{x {e}^{x} - {e}^{x}}{x} ^ 2 - 3$