1. [ includes endpoint ( doesn’t include endpoint
Interval Notation
[ includes endpoint
( doesn’t include endpoint

2. Example 1
Example 2 -1 4 3 5
3 ≤ x < 5
[3,5)
-1 ≤ x ≤ 4
[-1,4]

3. Note: -2 > x > 3 is not acceptable.
Example 3 -2 3
Note: -2 > x > 3 is not acceptable.
Note: Always use a parentheses for infinity.

4. Example 4 5
Note: 0 > x ≥ 5 is not acceptable since there is no value of x that can be less than 0 and greater than 5.

5. Practice Problems in class:
Write each given interval in interval notation: -1 3 6