A Junior pillow rumpled bedspread a stuffed animal We use a special character to say that something is an element of a set. To learn more about set notation review the lesson Set Notation. A set is a collection of things usually numbers.
In this form set-builder notation has three parts.
The second set describes integers from -3 to 8 9 is not included. Integers in both sets are 5 6 7 and 8. If the set contains more than one element then every two elements are separated by a comma symbol. The second set describes integers from -3 to 8 9 is not included.