# How would you find the first derivative of f(x) = (5-x)x^(2/3)?

$f ' \left(x\right) = - 1 \cdot {x}^{\frac{2}{3}} + \left(5 - x\right) \frac{2}{3} {x}^{- \frac{1}{3}} =$
$= - {x}^{\frac{2}{3}} + \frac{10}{3} {x}^{- \frac{1}{3}} - \frac{2}{3} {x}^{\frac{2}{3}} =$
$= - {x}^{\frac{2}{3}} \left[1 + \frac{2}{3}\right] + \frac{10}{3} {x}^{- \frac{1}{3}} =$
$= - x \cdot {x}^{- \frac{1}{3}} \left[\frac{5}{3}\right] + \frac{10}{3} {x}^{- \frac{1}{3}} =$
$= - 5 \frac{x - 2}{3 \sqrt[3]{x}}$