Giúp bn ni vs 😍😍😍😍😐😐

Bài 3:

`A={x∈R||x|<=3}`

Mà: `|x|<=3`

`<=>`\(\left[ \begin{array}{l}\left \{ {{x≤3} \atop {x≥-3}} \right.\\\left \{ {{x≤-3} \atop {x≥3}} \right.(KTM)\end{array} \right.\) 

`=>-3<=x<=3`

`=>A=[-3;3]`

`B={x∈R|-5<x-1<=9}`

Mà: `-5<x-1<=9`

`<=>{(-5<x-1),(x-1<=9):}`

`<=>{(-4<x),(x<=10):}`

`=>-4<x<=10`

`=>B=(-4;10]`

Ta có:

`A∩B=[-3;3]`

A\B`=∅`

B\A=`(-4;-3)∪(3;10]`

R(A\B) là j vậy bn ??????