Задание 5. Найдите значение выражения: 2) \((\sqrt{18}-\sqrt{2})\cdot\sqrt{2}\); 4) \((\sqrt{50}+\sqrt{2})\cdot\sqrt{2}\); 6) \((\sqrt{27}+\sqrt{3})\cdot\sqrt{3}\); 8) \(\sqrt{7\cdot12}\cdot\sqrt{21}\); 10) \(\sqrt{7\cdot45}\cdot\sqrt{35}\); 12) \(\sqrt{13\cdot18}\cdot\sqrt{26}\).

1. \((\sqrt{18}-\sqrt{2})\sqrt{2}=\sqrt{36}-\sqrt{4}=6-2=4\).
2. \((\sqrt{50}+\sqrt{2})\sqrt{2}=\sqrt{100}+\sqrt{4}=10+2=12\).
3. \((\sqrt{27}+\sqrt{3})\sqrt{3}=\sqrt{81}+\sqrt{9}=9+3=12\).
4. \(\sqrt{7\cdot12}\cdot\sqrt{21}=\sqrt{7\cdot12\cdot21}=\sqrt{1764}=42\).
5. \(\sqrt{7\cdot45}\cdot\sqrt{35}=\sqrt{7\cdot45\cdot35}=\sqrt{11025}=105\).
6. \(\sqrt{13\cdot18}\cdot\sqrt{26}=\sqrt{13\cdot18\cdot26}=\sqrt{6084}=78\).

Ответ: 2) 4; 4) 12; 6) 12; 8) 42; 10) 105; 12) 78.