Section 3.1

Chapter 3

Objectives:

•Identify Ordered Pair

•Identify a Relation

•Identify the Domain and Range of a Relation

Ordered Pair

Ordered Pair: Given two related elements x and y. An ordered pair that represent x and y can be written as ( x, y ).

Example 1: ( 5, 3 ) is an ordered pair

Example 2: ( Asma, 10) is also an ordered pair.

Notes:

1. ( 5, 3 ) and ( 3, 5 ) are two different pairs

2. { 5 , 3 } is not an ordered pair

3. 5, 3 cannot be an ordered pair

Class Exercise 1 Which of the following is an ordered pair

a) { ½ , -3 } b) ( -3, ½ ) c) { ( 5, 0 ) }

d) ( 1 , - 5 ) e) -3, 6

Answer: b and d

Relation

Relation A set of ordered pairs is a relation

Example 1: 25,,100,,5,,5, ObaidRashidSaeedAhmad

is a relation.Domain

Domain: The set of all first elements in a relation is called the domain of the relation

Example 1: Find the domain of each relation

,16,0,12,5,4,2

1,5)

29,,32,,58,)

Bb

MichaelRashidAhmadAa

Domain of A = { Ahmad, Rashid, Michael }

Domain of B = { 5, -4, -12, -16 }

Range

Range: The set of all second elements in a relation is called the range of the relation

Example 1: Find the range of each relation

,16,0,12,5,4,2

1,5)

29,,32,,58,)

Bb

MichaelRashidAhmadAa

29,32,58AofRange

,0,5,

2

1BofRange

Class Exercise 2 Find the domain and range of each relation

AhmadAhmadAhmadAb

FujairahRAKSharjahDubaiDhabiAbua

,3,,2,,1)

2,,3,,3,,2,,1,)

AhmadAofRange

AofDomainb

Range

FujairahSharjahDubaiDhabiAbuDomaina

Answers

3,2,1)

,3,2,1

,,,)

:

Home Work

• Do All Assigned Home Work in the Syllabus