Answer
$f(x)=3x\sqrt[3]{x^2}$
Work Step by Step
Using the properties of radicals, the given equation, $
f(x)=\sqrt[3]{27x^5}
,$ simplifies to
\begin{array}{l}\require{cancel}
f(x)=\sqrt[3]{27x^3\cdot x^2}
\\\\
f(x)=\sqrt[3]{(3x)^3\cdot x^2}
\\\\
f(x)=3x\sqrt[3]{x^2}
\end{array}