1. Warm Up: Monday
You have 15 minutes to complete your homework from Friday. When you are finished, please bring it to me to be graded.

2. Essential Question
How can we determine if a set of data is a function by using domain and range?

3. Vocab
Domain
Range
Input
Output
Function

4. Objectives The student will be able to:
1. To determine if a relation is a function.
2. To find the value of a function.
SOL: A.7aef
Designed by Skip Tyler, Varina High School

5. Functions
A function is a relation in which each element of the domain is paired with exactly one element of the range. Another way of saying it is that there is one and only one output (y) with each input (x).
f(x) y x

6. Function Notation
Input
Name of Function
Output

7. Determine whether each relation is a function.
1. {(2, 3), (3, 0), (5, 2), (4, 3)}
YES, every domain is different!
f(x) 2 3
f(x) 3
f(x) 5 2
f(x) 4 3

8. Determine whether the relation is a function.
2. {(4, 1), (5, 2), (5, 3), (6, 6), (1, 9)}
f(x) 4 1
f(x) 5 2
NO, 5 is paired with 2 numbers!
f(x) 5 3
f(x) 6
f(x) 1 9

9. Is this relation a function? {(1,3), (2,3), (3,3)}
Yes No
Answer Now

10. Vertical Line Test (pencil test)
If any vertical line passes through more than one point of the graph, then that relation is not a function.
Are these functions?
FUNCTION!
FUNCTION!
NOPE!

11. Vertical Line Test
FUNCTION!
NO!
NO WAY!
FUNCTION!

12. Is this a graph of a function?
Yes No
Answer Now

13. 3(3)-2 3 7 -2 -8 3(-2)-2 Given f(x) = 3x - 2, find: 1) f(3) = 7
= -8
3(-2)-2 -2 -8

14. Given h(z) = z2 - 4z + 9, find h(-3)
(-3)2-4(-3)+9 -3 30
h(-3) = 30

15. Given g(x) = x2 – 2, find g(4) 2 6 14 18
Answer Now

16. Given f(x) = 2x + 1, find -4[f(3) – f(1)]
-40
-16 -8 4
Answer Now