Algebra 2
Algebra 2
Relations and Functions
Lesson 2-1
Additional Examples
Algebra 2
Graph the relation {(–3, 3), (2, 2), (–2, –2), (0, 4), (1, –2)}.
Graph and label each ordered pair.
Algebra 2
Relations and Functions
Lesson 2-1
Algebra 2
Additional Examples
Write the ordered pairs for the relation. Find the domain
and range.
{(–4, 4), (–3, –2), (–2, 4), (2, –4), (3, 2)}
The domain is {–4, –3, –2, 2, 3}.
The range is {–4, –2, 2, 4}.
Relations and Functions
Lesson 2-1
Additional Examples
Algebra 2
Make a mapping diagram for the relation {(–1, 7), (1, 3),
(1, 7), (–1, 3)}.
Pair the domain elements with the range elements.
Algebra 2
Relations and Functions
Lesson 2-1
Additional Examples
Algebra 2
Use the vertical-line test to determine whether the graph
represents a function.
If you move an edge of a ruler from left to right
across the graph, keeping the edge vertical as
you do so, you see that the edge of the ruler
never intersects the graph in more than one point
in any position.
Therefore, the graph does represent a function.
Algebra 2
Algebra 2
Use the vertical-line test to determine
whether the graph represents a function.
Relations and Functions
Lesson 2-1
Algebra 2
Additional Examples
Find ƒ(2) for each function.
a. ƒ(x) = –x2 + 1
ƒ(2) = –22 + 1 = –4 + 1 = –3
b. ƒ(x) = |3x|
ƒ(2) = |3 • 2| = |6| = 6
9
c. ƒ(x) = 1 – x
9
9
ƒ(2) = 1 – 2 = –1 = –9
Algebra 2