Answer
$-\sqrt[3]{4}$
Work Step by Step
Recall:
For any real numbers $a, b, $ and $c$,
$$a(b+c)=ab+ac$$
Use the rule above to obtain:
\begin{align*}
\sqrt[3]{4}-2\sqrt[3]{4}&=(1-2)\sqrt[3]{4}\\
&=-1\sqrt[3]{4}\\
&=-\sqrt[3]{4}
\end{align*}