Answer
$-2\sqrt[3] 3$
Work Step by Step
$3\sqrt[3] 24-2\sqrt[3] 192=3\sqrt[3] (8\times3)-2\sqrt[3] (64\times3)=3\times\sqrt[3] 8\times\sqrt[3] 3-2\times\sqrt[3] 64\times\sqrt[3] 3=3\times2\times\sqrt[3] 3-2\times4\times\sqrt[3] 3=6\sqrt[3] 3-8\sqrt[3] 3=-2\sqrt[3] 3$