Giúp e vs ạ em cần gấp cảm ơn mng

Đáp án:+Giải thích các bước giải:

 `9 . (3+2sqrt3)/sqrt3 + (2+sqrt2)/(sqrt2+1) - (2+sqrt3)`

`=(sqrt3(sqrt3+2))/sqrt3 + (sqrt2(sqrt2+1))/(sqrt2+1) -2-sqrt3`

`=sqrt3+2 +sqrt2 -2-sqrt3`

`=sqrt2`

`10 . (sqrt160 -sqrt80)/(sqrt8-2) - (sqrt40-sqrt15)/(2sqrt2-sqrt3)`

`=(sqrt20(sqrt8-sqrt4))/(sqrt8-sqrt4) - (sqrt5(sqrt8 -sqrt3))/(sqrt8-sqrt3)`

`=2sqrt5 -sqrt5`

`=sqrt5`

`11. (1-(5+sqrt5)/(1+sqrt5)) ((5-sqrt5)/(1-sqrt5)-1)`

`=(1-(sqrt5(sqrt5+1))/(1+sqrt5))((sqrt5(sqrt5-1))/(-(sqrt5-1)) -1)`

`=(1-sqrt5)(-sqrt5-1)`

`=(sqrt5-1)(sqrt5+1)`

`=5 -1`

`=4`

`12. ((5-2sqrt5)/(2-sqrt5)-2) ((5+3sqrt5)/(3+sqrt5-2)`

`=((sqrt5(sqrt5-2))/(-(sqrt5-2))-2)((sqrt5(sqrt5+3))/(3+sqrt5)-2)`

`=(-sqrt5-2)(sqrt5-2)`

`=(sqrt5+2)(2-sqrt5)`

`=4-5`

`=-1.`