Answer
$y={(\frac{x}{3})}^\frac{2}{3}$, x $\geq$ 0
Work Step by Step
Apply the horizontal line test to check that the function has an inverse. Find the inverse.
$y=3x\sqrt x$
$x=3y\sqrt y$ (Interchange x and y, also x $\geq$ 0)
$x^2=9y^3$
$y={(\frac{x}{3})}^\frac{2}{3}$, x $\geq$ 0
