`17, sqrt{11+2sqrt{18}}`
`=sqrt{9+2.3sqrt{2}+2}`
`=sqrt{(3+sqrt{2})^2}`
`=|3+sqrt{2}|`
`=3+sqrt{2}`
`21, sqrt{9+4sqrt{5}}`
`=sqrt{5+4sqrt{5}+4}`
`=sqrt{(sqrt{5}+2)^2}`
`=|\sqrt{5}+2|`
`=sqrt{5}+2`
`25, sqrt{12+2sqrt{35}}`
`=sqrt{7+2sqrt{7}.sqrt{5}+5}`
`=sqrt{(sqrt{7}+sqrt{5})^2}`
`=|sqrt{7}+sqrt{5}|`
`=sqrt{7}+sqrt{5}`
`29,33, sqrt{14+-8sqrt{3}}`
`=sqrt{14+-2sqrt{48}}`
`=sqrt{8+-2sqrt{8}.sqrt{6}+6}`
`=sqrt{(sqrt{8}+-sqrt{6})^2}`
`=2sqrt{2}+-sqrt{6}`
`37, sqrt{21+6sqrt{6}}`
`=sqrt{18+2.3sqrt{2}.sqrt{3}+3}`
`=sqrt{(3sqrt{2}+sqrt{3})^2}`
`=3sqrt{2}+sqrt{3}`
`41, sqrt{29-12sqrt{5}}`
`=sqrt{20-2.2sqrt{5}.3+9}`
`=sqrt{(2sqrt{5}-3)^2}`
`=2sqrt{5}-3`
`45, sqrt{36-12sqrt{5}}`
`=sqrt{30-2.sqrt{6.5}.sqrt{6}+6}`
`=sqrt{(sqrt{30}-sqrt{6})^2}`
`=sqrt{30}-sqrt{6}`
`49, sqrt{49-20sqrt{6}}`
`=sqrt{25-2.5.2sqrt{6}+24}`
`=sqrt{(5-2sqrt{6})^2}`
`=5-2sqrt{6}`
