22) √72 · 3√12

Упрощаем корни: \(\sqrt{72}=6\sqrt{2}\), \(\sqrt{12}=2\sqrt{3}\).

\(\sqrt{72}\cdot3\sqrt{12}=6\sqrt{2}\cdot3\cdot2\sqrt{3}=36\sqrt{6}\).

Ответ: \(36\sqrt{6}\).