September 23, 2015
Warm Up:
Generate ordered pairs for the function y = -2
-2, -1, 0, 1, and 2. Graph the ordered pairs.
x
-2
-1
0
1
2
y
x + 1 for x =
September 23, 2015
4.2: Relations and Functions
Learning Target
* I can find the domain and range of both
discrete and continuous functions
* I will be able to identify a function
Homework
p. 243
#1-14, 19-21
September 23, 2015
Definition of a relation:
a relationship that is
represented by a set
of ordered pairs.
September 23, 2015
Multiple Representations of Relations
September 23, 2015
Relations: A set of ordered pairs.
ex. { (-2, 1) , (-1, 2) , (0, 3) , (1, 4) , (2, 5) }
Discrete or
Continuous
A relation can be represented in several different ways:
1. Table:
x
2. Graph:
3. Mapping diagram:
y
-2
-1
0
1
2
-2
-1
0
1
2
1
2
3
4
5
September 23, 2015
Definition of a Function:
A Function is a relationship between two variables such that
each value of the first variable is paired with exactly one value
The "x" value never repeats
The domain of a function is the set of all
possible x values
The range of a function is the set of all
possible y values
September 23, 2015
ex. { (-2, 1) , (-1, 2) , (0, 3) , (1, 4) , (2, 5) }
domain: the set of the first coordinates (x values)
range: the set of the second coordinates (y values)
September 23, 2015
Give the Domain and Range of each relation in the Mapping Diagrams.
Function?
Function?
Domain:
Range:
Function?
Domain:
Range:
Function?
Domain:
Range:
Function?
Domain:
Range:
September 23, 2015
Determine if each relation is a function:
Then state the domain and range
no
x y
5 2
8 7
3 2
5 -2
Domain:
Range:
yes
x y
4 5
3 9
2 0
1 -2
Domain:
Range:
no
x y
-8 0
4 0
3 0
4 0
Domain:
Range:
September 23, 2015
example:
x
Express the relation { (2,3), (4,7), (6,8) } as a table, graph,
and a mapping diagram. Then give the domain and range.
y
domain:
range:
function?
September 23, 2015
Give the domain and range of each graph.
Domain:
Range:
Domain:
Range:
September 23, 2015
Give the domain and range of each graph.
Domain:
Domain:
Range:
Range: