Algebra 2Algebra 2
Algebra 2Algebra 2
Algebra 2Algebra 2
Graph the relation {(–3, 3), (2, 2), (–2, –2), (0, 4), (1, –2)}.
Lesson 2-1
Relations and FunctionsRelations and Functions
Graph and label each ordered pair.
Additional Examples
Algebra 2Algebra 2
Algebra 2Algebra 2Lesson 2-1
Relations and FunctionsRelations and Functions
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}.
Additional Examples
Algebra 2Algebra 2Lesson 2-1
Relations and FunctionsRelations and Functions
Make a mapping diagram for the relation {(–1, 7), (1, 3),
(1, 7), (–1, 3)}.
Pair the domain elements with the range elements.
Additional Examples
Algebra 2Algebra 2
Algebra 2Algebra 2Lesson 2-1
Relations and FunctionsRelations and Functions
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.
Additional Examples
Algebra 2Algebra 2
Algebra 2Algebra 2
Use the vertical-line test to determine
whether the graph represents a function.
Algebra 2Algebra 2Lesson 2-1
Relations and FunctionsRelations and Functions
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
c. ƒ(x) = 9
1 – x
ƒ(2) = = = –99
1 – 29
–1
Additional Examples
Algebra 2Algebra 2