Answer
$3-2\sqrt[3]{3}$
Work Step by Step
Using $a(b+c)=ab+ac$, or the Distributive Property, and the properties of radicals, the given expression, $
\sqrt[3]{3}(\sqrt[3]{9}-\sqrt[3]{8})
,$ simplifies to
\begin{array}{l}\require{cancel}
\sqrt[3]{3}(\sqrt[3]{9})-\sqrt[3]{3}(\sqrt[3]{8})
\\\\=
\sqrt[3]{27}-\sqrt[3]{24}
\\\\=
\sqrt[3]{27}-\sqrt[3]{8\cdot3}
\\\\=
\sqrt[3]{(3)^3}-\sqrt[3]{(2)^3\cdot3}
\\\\=
3-2\sqrt[3]{3}
.\end{array}