Interval Notation

Interval notation is a mathematical notation used to represent a range of values on the number line. It uses parentheses and brackets to indicate whether endpoints are included or excluded.

It represents all real numbers less than or equal to 'a'. The parenthesis indicates that 'a' is included in the interval.

The inequality notation is \(a < x \leq b\).

It represents all real numbers 'x' such that 'x' is greater than or equal to 'a' and less than 'b'.

The interval notation is \((5, \infty)\).

The number -3 is included in the interval (closed), while 2 is not included (open).

The interval notation is \((-\infty, 10]\).

Open intervals do not include their endpoints (e.g., \((a, b)\)), while closed intervals do include their endpoints (e.g., \([a, b]\)).

The interval notation is \((-\infty, 20)\).

It signifies all real numbers 'x' such that 'a < x < b', meaning 'a' and 'b' are not included.