4. Solving Inequalities with Absolute Values
For inequalities involving absolute values ie. |x|, we use the following relationships, for some number n:
If `|f(x)| > n`, then this means:
`f(x) < -n` or `f(x) > n`
If `|f(x)| < n`, then this means:
`-n < f(x) < n`
Example 1
Solve the inequality |x − 3| < 2.
Answer
Applying the relationships discussed above:
`- 2 < x - 3 < 2`
Adding `3` to all sides, we get:
`-2 + 3 < x - 3 + 3 < 2 + 3`
`1 < x < 5`
Here is the graph of our solution: