Question

Verbal

4. When describing sets of numbers using interval notation, when do you use a parenthesis and when do you use a bracket?

Answer 1

Explanation:

A parenthesis is used when the number next to it is NOT part of the solution set

like : all numbers up to but not including 3 .

Parens are always next to infinity when it is part of the solution set .

A bracket is used when the number next to it is included in the solution set.