Function Notation 

In math, function notation is used to show the independent variable in a function for example, f(x) means that the value of the function f depends on the value of the independent variable x.

Example 1

f(x) = 2x + 3

Input 5 into the x.

f(5) = 2(5) + 3

Write the equation with 5 where the x’s are.

f(5) = 13

Solve the equation.

The symbol f(x) provides a formula for the function f, and represents the value of the function for a given value of x.

Example 2 

f(x) = 5x – 7

Input 2 into the x.

f(2) = 5(2) – 7

Write the equation with 2 where the x’s are.

f(2) = 3

Solve the equation.

Why

Function notation is an efficient way to write functions that is easy to read and understand. It allows you to easily see the input value for the independent variable inside the parentheses.

Vocabulary

Independent variable- A variable that represents a quantity that does not depend on any other variable for its value.

Function- A mathematical relationship between two variables, where every input variable has one output variable.