1) (x-1)(x+3)>0
x=1 x= -3
+ - +
------- -3 ---------- 1 ------------
\\\\\\\\\ \\\\\\\\\\\\\\\
x∈(-∞; -3)U(1; +∞)
3) (x+1.5)(x-2)x>0
x= -1.5 x=2 x=0
- + - +
------- -1.5 ----------- 0 ------------ 2 ------------
\\\\\\\\\\\\\\ \\\\\\\\\\\\\\
x∈(-1.5; 0)U(2; +∞)
2) (x+4)(x-2)<0<br>x= -4 x=2
+ - +
--------- -4 ----------- 2 ------------
\\\\\\\\\\\\\\
x∈(-4; 2)