When the variable name in a function is replaced with another function, the result is called a
composite function. If
then
f [
g(
x)] is a composite function. The statement
f[
g(
x)] is read “
f of
g of
x” or “the composition of
f with
g.”
f [
g(
x)] can also be written as
The symbol between
f and
g is a small open circle.
Example 1: If
f (
x) = 3
x + 2 and
g(
x) = 4
x − 5, find each of the following.
From the previous example, notice that
f[
g(
x)] and
g[
f(
x)] are not equal.
Example 2: If
f(
x) = 3
x2 + 2
x + 1 and
g(
x) = 4
x − 5, find each of the following.
Linear Sentences in One Variable
Relations and Functions
