1. Functions and Their Graphs Section 3.1 1

2. Relation A relation is a correspondence between two sets. CourseCourse Number Chemistry (CHEM)111 English (ENGL)111 L Math (MATH)121 History (HIST)140 2

3. Ordered Pairs We can express the previous relation in this way: { (CHEM,111), (CHEM,111L), (ENGL,111), (MATH, 140), (HIST,121) } The set of first elements (CHEM,ENGL,MATH,HIST) is the domain. The set of second elements (111,111L,121,140) is the range. 3

4. Function A relation is said to be a function if any element from the domain is associated with only ONE element from the range. Example: { (CHEM,111), (CHEM,111L), (ENGL,111), (MATH, 140), (HIST,121) } 1.Is ENGL associated with only one element in the range? 2.Is CHEM associated with only one element in the range? Is this relation a function? 4

5. Which of these relations are functions? 1.{ (Martin, 731), (Dickson, 615), (Jackson, 731), (Dover,931) } 2.{ (731, Martin), (615, Dickson), (731, Jackson), (931, Dover) } 5

6. Exercise 33 – Page 217 6

7. Exercise 28 – page 217 7

8. Your Turn 8

9. 9

10. Exercise 83 – Page 218 10

11. Domain of a function 11

12. 12

13. Exercise 51 – page 217 13

14. Exercise 55 – page 217 14

15. Exercise 59 – page 217 15

16. Exercise 47 – page 217 16

17. Your Turn 17

18. Domain in Application 18

19. Function Operations 19

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