The functions f and g are defined as follows.

Step-by-step explanation:

By definition, a relation is a function if and only if each input value have one and only one output value.

The input values are the x-values and the output values are the y-values.

Given the function f(x):

You need to substitute into this function:

And now you must evaluate in order to find the corresponding output value.

You get:

The function g(x) is:

Then, you need to substitute in the function:

And  finally you must evaluate in order to find the corresponding output value. This is: