Answer
$6x$
Work Step by Step
RECALL:
The quotient rule:
$\dfrac{\sqrt[n]{a}}{\sqrt[n]{b}}=\sqrt[n]{\dfrac{a}{b}}$
where
$\sqrt[n]{a}$ and $\sqrt[n]{b}$ are real numbers and $b\ne0$
Use the rule above to obtain:
$\require{cancel}=\sqrt{\dfrac{72x^3}{2x}}
\\=\sqrt{\dfrac{36\cancel{72}\cancel{x^3}x^2}{\cancel{2x}}}
\\=\sqrt{36x^2}
\\=\sqrt{(6x)^2}$
Simplify to obtain:
$=6x$