solve the inequalities

Ans:



It is a simple quadratic function with root 3 & 4.
Simply draw the graph of f(x)
f(x) < 0 for 3 < x < 4
And similarly draw the graph of |f(x)|
|f(x)| > 0 for 3 < x < 4
And in the region x < 3 & x > 4
f(x) = |f(x)|
Solution:
3 < x < 4