The inequality is .

Step 1:

Solve the quadratic equation

                      (Related function)

                     (Factor)

or               (Zero productive property)

or                       (Simplify)

Step 2:

Plot and on a number line.

Observe the graph:

The number line divide into three intervals.

Step 3: Test a value from each interval of the original inequality.

Case (i): .

                      (Original function)

       (Substitute )

            (Evaluate powers: )

                    (Multiply)

                                      (Simplify)

Case (ii): .

                      (Original function)

                 (Substitute )

                     (Evaluate powers: )

                          (Multiply)

                                     (Simplify)

Case (iii):  .

                      (Original function)

                 (Substitute )

                   (Evaluate powers: )

                     (Multiply)

                                     (Simplify)

Hence, the solution set is .

It is shown on the number line.

Solution set is .