1. $(2+2+2)\sqrt{5}$
$6\sqrt{5}$
2. $-5\sqrt{3}-3\sqrt{6}$
3. $-3\sqrt{2}+6\sqrt{5}$
4. $-\sqrt{3}-5\sqrt{6}$
5. $\sqrt{2}-3\sqrt{9\cdot 2}$
$\sqrt{2}-3\cdot 3\sqrt{2}$
$-8\sqrt{2}$
6. $-\sqrt{6\cdot 9}-3\sqrt{6}+3\sqrt{9\cdot 3}$
$-3\sqrt{6}-3\sqrt{6}+3\cdot 3\sqrt{3}$
$-6\sqrt{6}+9\sqrt{3}$
7. $-3\sqrt{6}-\sqrt{4\cdot 3}+3\sqrt{3}$
$-3\sqrt{6}-2\sqrt{3}+3\sqrt{3}$
$-3\sqrt{6}+\sqrt{3}$
8. $-2\sqrt{5}-2\sqrt{6\cdot 9}$
$-2\sqrt{5}-2\cdot 3\sqrt{6}$
$-2\sqrt{5}-6\sqrt{6}$
9. $3\sqrt{2}+2\sqrt{4\cdot 2}-3\sqrt{2\cdot 9}$
$3\sqrt{2}+2\cdot 2\sqrt{2}-3\cdot 3\sqrt{2}$
$3\sqrt{2}+4\sqrt{2}-9\sqrt{2}$
$-2\sqrt{2}$
10. $4\sqrt{20}-\sqrt{3}$
$4\sqrt{4\cdot 5}-\sqrt{3}$
$4\cdot 2\sqrt{5}-\sqrt{3}$
$8\sqrt{5}-\sqrt{3}$
11. $3\sqrt{9\cdot 2}-4\sqrt{2}$
$3\cdot 3\sqrt{2}-4\sqrt{2}$
$9\sqrt{2}-4\sqrt{2}\Rightarrow 5\sqrt{2}$
12. $-3\sqrt{9\cdot 3}+2\sqrt{3}-\sqrt{4\cdot 3}$
$-3\cdot 3\sqrt{3}+2\sqrt{3}-2\sqrt{3}$
$-9\sqrt{3}$
13. $-3\sqrt{6}-\sqrt{3}$
14. $-3\sqrt{2}+3\sqrt{4\cdot 2}+3\sqrt{6}$
$-3\sqrt{2}+3\cdot 2\sqrt{2}+3\sqrt{6}$
$3\sqrt{2}+3\sqrt{6}$
15. $-2\sqrt{9\cdot 2}-3\sqrt{4\cdot 2}-\sqrt{4\cdot 5}+2\sqrt{4\cdot 5}$
$-6\sqrt{2}-6\sqrt{2}-2\sqrt{5}+4\sqrt{5}$
$-12\sqrt{2}+2\sqrt{5}$
16. $-3\sqrt{9\cdot 2}+3\sqrt{8}$
$-9\sqrt{2}+3\sqrt{4\cdot 2}$
$-9\sqrt{2}+6\sqrt{2}$
$-3\sqrt{2}$
17. $-2\sqrt{4\cdot 6}+2\sqrt{5\cdot 4}$
$-4\sqrt{6}+4\sqrt{5}$
18. $-3\sqrt{4\cdot 2}-\sqrt{5}-3\sqrt{6}+2\sqrt{9\cdot 2}$
$-6\sqrt{2}-\sqrt{5}-3\sqrt{6}+6\sqrt{2}$
$-\sqrt{5}-3\sqrt{6}$
19. $3\sqrt{6\cdot 4}-3\sqrt{3\cdot 9}+2\sqrt{6}+2\sqrt{2\cdot 4}$
$6\sqrt{6}-9\sqrt{3}+2\sqrt{6}+4\sqrt{2}$
$4\sqrt{2}-9\sqrt{3}+8\sqrt{6}$
20. $2\sqrt{6}-\sqrt{9\cdot 6}-3\sqrt{9\cdot 3}-\sqrt{3}$
$2\sqrt{6}-3\sqrt{6}-9\sqrt{3}-\sqrt{3}$
$-\sqrt{6}-10\sqrt{3}$