We can write the domain and range in interval notation which uses values within brackets to describe a set of numbers in interval notation we use a square bracket [ when the set includes the endpoint and a parenthesis ( to include that the endpoint is either not included or the interval is unbounded for example if a person has $100 to spend he or she would need to express the interval that is more than 0 and less than or equal to 100 and write (0, 100]. We will discuss interval notation in greater detail later
