`a)` `(sqrt27-3sqrt2+2sqrt6):3sqrt3`
`=(3sqrt3-3sqrt2+2sqrt6):3sqrt3`
`=1-sqrt6/3+(2sqrt2)/3`
`=(3-sqrt6)/3 +(2sqrt2)/3`
`=(3-sqrt6 +2sqrt2)/3`
`b)` `sqrt{(sqrt3+1)^2}+sqrt{(1-sqrt3)^2}`
`=|sqrt3+1|+|1-sqrt3|`
`=sqrt3+1+sqrt3-1` `(Vì ` `sqrt3+1>0` `;` `1-sqrt3<0` `)`
`=2sqrt3`
`c)` `(sqrt2+1)^2+(sqrt2-1)^2`
`=(sqrt2)^2+2*sqrt2*1+1^2+(sqrt2)^2-2*sqrt2*1+1^2`
`=2+2sqrt2+1+2-2sqrt2+1`
`=3+3`
`=6`
`d)` `(sqrt3+1)^2+(1-sqrt3)^2`
`=(sqrt3)^2+2*sqrt3*1+1^2+1^2-2*sqrt2*1+(sqrt3)^2`
`=3+2sqrt3+1+1-2sqrt2+3`
`=4+4`
`=8`
`e)` `sqrt{(sqrt2+1)^2}+sqrt{(1-sqrt2)^2}`
`=|sqrt2+1|+|1-sqrt2|`
`=sqrt2+1+sqrt2-1` `(Vì ` `sqrt2+1>0` `;` `1-sqrt2<0` `)`
`=2sqrt2`
