Đáp án:
$| x-2 | - 2x < 3$ .
$⇔ |x-2|<3+2x$
$⇔$$\left \{ {{x-2<3+2x} \atop {x-2>-3-2x}} \right.$ ⇔ $\left \{ {{x-2x-2-3<0} \atop {x-2+3+2x>0}} \right.$
$⇔$ $\left \{ {{-x-5<0} \atop {3x+1>0}} \right.$ ⇔ $\left \{ {{-x<5} \atop {3x>-1}} \right.$
$⇔$$\left \{ {{x>-5} \atop {x>-1/3}} \right.$ $⇔ x>-1/3$
Vậy $S=(-1/3; +∞)$
BẠN THAM KHẢO NHA!!!