Range of a function

The range of a function is the set of all possible values it can produce.
For example, consider the function No matter what value we give to x, the function is always positive:

So the range of the function is

"all real numbers greater than or equal to zero".


Ranges can be written out in words as above, but to be more mathematically precise they are also written using either inequalities, or in interval notation:

As a graph

graph of x squared If we plot the function above on a graph we see that for any value of x, the graph is either zero or positive - above the x axis.

Other functions topics