Đáp án:
`b) |x|<2`
`⇒x∈{1;0;-1}`
`e)|x+3|=0`
`Vì |0|=0`
`⇒x+3=0`
`⇒x=0-3`
`⇒x=-3`
`h) |x+2|= 12+(-3)+|-4|`
`⇒|x+2|=9+4`
`⇒|x+2|=13`
⇒\(\left[ \begin{array}{l}x+2=13\\x+2=-13\end{array} \right.\)
⇒\(\left[ \begin{array}{l}x=9\\x=-15\end{array} \right.\)
`o) |2x+3|=5`
⇒\(\left[ \begin{array}{l}2x+3=5\\2x+3=-5\end{array} \right.\)
⇒\(\left[ \begin{array}{l}2x=2\\2x=-8\end{array} \right.\)
⇒\(\left[ \begin{array}{l}x=1\\x=-4\end{array} \right.\)
