So is solution of the first inequality. Now, if we have
So is solution of the system. Finally, if then
which is impossible. That is, the solution set of the first inequality is (The idea is to solve and and study the inequality on each region you obtain.) Now, we will work with the second inequality. Write it as
Study the sign on , , , and You should obtain that the set solution is (The idea is to solve and and study the inequality on each region you obtain. Note that we can't divide by 0. So and Finally, one gets the intersection to obtain