Function Notation

Function Notation

Open Ended

State the range for the following relation.

Open Ended

State the domain for the following relation.

Poll

Is this relation a function

• yes

• no

Multiple Select

Select all the values for x so that g(x) is NOT a function

• 3

• 6

• 9

• 10

What is Function Notation?

Functions can be written 4 different ways: as a table, a mapping, a graph, and an equation.

An equation that is a function may be expressed using functional notation. 

The notation f(x) (read “f of (x)”) represents the variable y.

Table

The table shows the values for function f(x).

What is the value of f(0)?

What is the value of f(2)?

Table

The table shows the values for function f(x).

What is the value of f(0)?

What is the value of f(2)?

To find these values, we must find were x is 0 and where x is 2. We then must find the corresponding y value for those x values.

f(0)=0

f(2)=4

Multiple Choice

What is the value of f(3)?

• 3

• 1

• 2

• 5

Multiple Choice

What is the value of f(1)?

• 3

• 1

• 2

• 5

Graph

The graph shows function f(x).

What is the value of f(6)?

What is the value of f(10)?

Graph

The graph shows function f(x).

What is the value of f(6)?

What is the value of f(10)?

To find these values, we must find were x is 6 and where x is 10. We then must find the corresponding y value for those x values.

f(6)=0 f(10)= -2

Multiple Choice

What is the value of f(1)?

• 1

• 2

• 3

• 4

Multiple Choice

What is the value of f(-2)?

• 1

• 2

• 3

• 4

Function notation using an equation

f(x)=2x+6

Example:

y = 2x + 6 can be written as f(x) = 2x + 6.

Given the equation y = 2x + 6 , evaluate when x = 3.

y = 2x + 6

y = 2(3) + 6 

y = 12

Multiple Choice

Given f(x) = 4x + 8, find f(2)

• f(2)= 50

• f(2)= 16

• f(2)= 8

• f(2)= 4

Multiple Choice

Given f(x) = 4x + 8, find f(-2)

• f(-2)= 10

• f(-2)= 16

• f(-2)= 0

• f(-2)= -2

Multiple Choice

Given f(x) = 4x + 8, find f(4a)

• f(4a)=44a+8

• f(4a)=16a+8

• f(4a)=24a

• f(4a)=24

Multiple Choice

Given f(x) = 4x + 8, find f(4a+1)

• f(4a+1)=16a+8

• f(4a+1)=16a+ 4

• f(4a+1)=16a + 12

• f(4a+1)= 44a+1

Multiple Choice

For the function f(x) = -3x + 3 find f(0).

• 0
• -3
• 3
• -1

Multiple Choice

What is x if
f(x) = -2?

• 4
• 0
• 3
• 8

Multiple Choice

Evaluate f(-2) if f(x) = x²+ 3

• -1

• 1

• 7

• -7

Multiple Choice

Evaluate f(-2) if f(x) = x + 3

• -1
• 1
• 5
• -5

Multiple Choice

What is f(1)?

• 1
• 5
• 0
• 4

Multiple Choice

Given h(x) = 5 - 9x, find h(8). 

• h(8) = -360
• h(8) = -67

Multiple Choice

f(x) is the same thing as ______.

• y

• x

• input

• an equation