1) (x-7)(x? 3)<0<br>
2) 4x² >9
4x²-9>0
4(x²- 9/4)>0
x² - 9/4 >0
(x-3/2)(x+3/2)>0
x=3/2 x= -3/2
+ - +
------- -3/2 ------------ 3/2 ----------------
\\\\\\\\\\ \\\\\\\\\\\\\\\\\\\
x∈(-∞; -3/2)U(3/2; +∞)
3) 3x(x-15)<0<br>x(x-15)<0<br>x=0 x=15
+ - +
----------- 0 ------------- 15-----------
\\\\\\\\\\\\\\\\
x∈(0; 15)