Đáp án:
$\begin{array}{l}
Dkxd:\left\{ \begin{array}{l}
3x \ge 0\\
\sqrt[3]{{{x^2}}} - 4\# 0
\end{array} \right.\\
\Leftrightarrow \left\{ \begin{array}{l}
x \ge 0\\
\sqrt[3]{{{x^2}}}\# 4
\end{array} \right.\\
\Leftrightarrow \left\{ \begin{array}{l}
x \ge 0\\
{x^2}\# \sqrt[3]{4}
\end{array} \right.\\
\Leftrightarrow \left\{ \begin{array}{l}
x \ge 0\\
x\# \sqrt {\sqrt[3]{4}} \\
x\# - \sqrt {\sqrt[3]{4}}
\end{array} \right.\\
\Leftrightarrow \left\{ \begin{array}{l}
x \ge 0\\
x\# \sqrt[3]{2}\\
x\# - \sqrt[3]{2}
\end{array} \right.\\
\Leftrightarrow \left\{ \begin{array}{l}
x \ge 0\\
x\# \sqrt[3]{2}
\end{array} \right.\\
Vậy\,x \ge 0;x\# \sqrt[3]{2}
\end{array}$
