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