In interval notation we use a square bracket when the set includes the endpoint and a parenthesis to indicate that the endpoint is either not included or the interval is unbounded. So we are going to read our graph from bottom to top ie negative y-axis to positive y-axis and find all the y-values that are allowed for our graph. In the previous examples we used inequalities and lists to describe the domain of functions.
Domain and Range of a Function.
Similarly the range is the set of all second elements or y-values. So we are going to read our graph from bottom to top ie negative y-axis to positive y-axis and find all the y-values that are allowed for our graph. If the domain of a function is all real numbers ie. Using set-builder notation it is written.