Question

Answer 1

\(a.x\in\left\{-2;-1;0;1\right\}\)

\(b.x\in\left\{-3;-2;-1;0\right\}\)

Answer 2

a) -3<x<2

Answer 3

a) \(\dfrac{-3}{7}< \dfrac{x}{7}< \dfrac{2}{7}\)=>-3<x<2=>x∈{-2;-1;0;1}

b) \(\dfrac{4}{-3}< \dfrac{x}{-3}< \dfrac{1}{3}\)=>\(\dfrac{4}{-3}< \dfrac{x}{-3}< \dfrac{-1}{-3}\)=>4<x<-1 (vô lý)=>x∈∅