`ĐK: m > 2`
`a)`
Để `A ⊂ B`
`<=>` \(\left\{ \begin{array}{l}m + 2 < 3\\m + 2 < 2m\end{array} \right.\)
`<=>` \(\left[ \begin{array}{l}m < 1 (l)\\m > 2\end{array} \right.\)
`=> m > 2`
`b)`
Để `A ∩ B ne ∅`
Xét `2TH:`
`-` \(\left\{ \begin{array}{l}m + 2 < 3\\m + 2 < 2m\end{array} \right.\)
`<=>` \(\left[ \begin{array}{l}m < 1 (l)\\m > 2\end{array} \right.\)
`=> m > 2`
`-` \(\left\{ \begin{array}{l}m + 2 > 3\\m + 2 > 2m\end{array} \right.\)
`<=>` \(\left[ \begin{array}{l}m > 1 \\m < 2(l)\end{array} \right.\)
`=> 1 < m < 2`
`=> m ∈ (1; 2)`
