Answer
$3\sqrt[3]{2}$
Work Step by Step
Using $\sqrt[n]{x}\cdot\sqrt[n]{y}=\sqrt[n]{xy},$ the given expression is equivalent to:
\begin{align*}
&
=\sqrt[3]{3(18)}
\\&=
\sqrt[3]{54}
\end{align*}
Extracting the root of the factors that is a perfect power of the index, the expression above is equivalent to
\begin{align*}
&
=\sqrt[3]{27\cdot2}
\\&=
\sqrt[3]{(3)^3\cdot2}
\\&=
3\sqrt[3]{2}
.\end{align*}
Hence, the simplified form of the given expression is $
3\sqrt[3]{2}
$.
