Answer
$13\sqrt[3]{7}+\sqrt{3}$
Work Step by Step
By combining like radicals, the given expression, $
9\sqrt[3]{7}-\sqrt[]{3}+4\sqrt[3]{7}+2\sqrt{3}
,$ simplifies to
\begin{array}{l}\require{cancel}
( 9\sqrt[3]{7}+4\sqrt[3]{7})+(-\sqrt[]{3}+2\sqrt{3})
\\\\=
13\sqrt[3]{7}+\sqrt{3}
.\end{array}