1. Suppose that you have a two-variable relationship…
– ALGEBRA I –
Unit 1 – Section 3
Function Notation
Suppose that you have a two-variable relationship…
To generate ordered pairs, you need to choose values for “x” and evaluate…

2. Here is a table to illustrate some answers:
– ALGEBRA I –
Unit 1 – Section 3
Function Notation
Here is a table to illustrate some answers: X
Work Y
Ordered Pair 4
2(4) + 6 = = 14 14
(4, 14) 9
2(9) + 6 = = 24 24
(9, 24)
2(0) + 6 = = 6 6
(0, 6) 3
2(3) + 6 = = 12 12
(3, 12)

3. Let’s talk about functions notation in a little more detail…
– ALGEBRA I –
Unit 1 – Section 3
Function Notation
To change this to function notation, it is just a matter of switching the variable…
Let’s talk about functions notation in a little more detail…

4. Function Notation This is read as “f of x”. FUNCTION NOTATION –
an alternative way to write an equation that allows you to “name” different equations values that are input into a function
Independent Variable
Function Name
This is read as “f of x”.

5. What is the purpose of writing a relationship in function notation?
1. Function notation allows you distinguish that a relationship is a function and has the caveat that each member of the domain matches with exactly on value in the range.
Function (or an equation)
Just an equation (not a function)

6. What is the purpose of writing a relationship in function notation?
2. Function notation allows you to give a relationship a “name” and distinguish between different relationships.
This shows that there are three distinct relationships.
Are all of the “y’s” referring to same thing?

7. Suppose that you are given a problem like the following…
Function Notation
Suppose that you are given a problem like the following…
This means that you need to plug 3 in for “x” and simplify. It is just like evaluating an expression.
The ordered pair would be:

8. Suppose that you are given a problem like the following…
Function Notation
Suppose that you are given a problem like the following…
This means that you need to plug 9 in for “x” and simplify. It is just like evaluating an expression.
The ordered pair would be:

9. Function Notation
Notice that the process is exactly same as if you were still using “y’s” rather than “f(x)’s”… You can compare the charts… X
Work Y
Ordered Pair 4
2(4) + 6 = = 14 14
(4, 14) 9
2(9) + 6 = = 24 24
(9, 24)
2(0) + 6 = = 6 6
(0, 6) 3
2(3) + 6 = = 12 12
(3, 12)

10. Function Notation
Notice that the process is exactly same as if you were still using “y’s” rather than “f(x)’s”… You can compare the charts… X
Work
F(x)
Ordered Pair 4
2(4) + 6 = = 14 14
(4, 14) 9
2(9) + 6 = = 24 24
(9, 24)
2(0) + 6 = = 6 6
(0, 6) 3
2(3) + 6 = = 12 12
(3, 12)

11. Evaluate the following functions.
Try These Problems…
Evaluate the following functions.
1. f(x) = 5x2 Find f(3).
2. g(y) = 5y Find g(0).
3. h(t) = 2t – 9 Find h(20).
4. T(x) = 3x3 – 4x Find T(2).
**The answers can be found at the end of the PowerPoint.

12. ALGEBRA IS FUN AND EASY!
**Answers: 1) ) ) ) 16