CH AP TER 1
Preparation for Calculus
Section 1.1 Graphs and Models ............................................................................ 2
Section 1.2 Linear Models and Rates of Change ................................................. 11
Section 1.3 Functions and Their Graphs ............................................................. 22
Section 1.4 Review of Trigonometric Functions ................................................. 36
Section 1.5 Inverse Functions ............................................................................ 45
Section 1.6 Exponential and Logarithmic Functions ........................................... 62
Review Exercises ................................................................................................... 72
Problem Solving .................................................................................................... 87
,C H A P T E R 1
Preparation for Calculus
Section 1.1 Graphs and Models
1. To find the x-intercepts of the graph of an equation, 8. y 5 2x
let y be zero and solve the equation for x. To find the
x 1 0 1 2 5
3 4
y-intercepts of the graph of an equation, let x be zero 2
and solve the equation for y. y 7 5 3 1 0 1 3
2. Symmetry helps in sketching a graph because you need
only half as many points to plot. Answers will vary.
3. y 32 x 3
x-intercept: 2, 0
y-intercept: 0, 3
Matches graph (b).
4. y 9 x2 9. y 4 x2
x-intercepts: 3, 0, 3, 0 x 3 2 0 2 3
y-intercept: 0, 3 y 5 0 4 0 5
Matches graph (d).
5. y 3 x2
x-intercepts:
3, 0 , 3, 0
y-intercept: 0, 3
Matches graph (a).
6. y x3 x
10. y x 3
2
x-intercepts: 0, 0, 1, 0, 1, 0
y-intercept: 0, 0 x 0 1 2 3 4 5 6
Matches graph (c). y 9 4 1 0 1 4 9
7. y 1x
2
2
x 4 2 0 2 4
y 0 1 2 3 4
2
, Section 1.1 Graphs and Mͅ odels 3
11. y x 1 3
15. y
x
x −4 −3 −2 −1 0 1 2
x 3 2 1 0 1 2 3
y 3 2 1 0 1 2 3
y 1 32 3 Undef. 3 3
2
1
12. y x 1
x 3 2 1 0 1 2 3 1
16. y
y 2 1 0 1 0 1 2 x 2
x 6 4 3 2 1 0 2
y 14 12 1 Undef. 1 1
2
1
4
13. y x 6
x 0 1 4 9 16
y 6 5 4 3 2 17. y 5 x
(a) 2, y 2, 1.73 y 52 3 1.73
14. y x 2
(b) x, 3 4, 3 3 5 4
x 2 1 0 2 7 14 18. y x5 5x
y 0 1 2 2 3 4
(a) 0.5, y 0.5, 2.47
(b) x, 4 1.65, 4 and x, 4 1, 4
, 4 Chapter 1 Preparation for Calculus
19. y 2 x 5
25. y 2 x
y-intercept: y 20 5 5; 0, 5 5x 1
2 0
x-intercept: 0 2x 5 y-intercept: y 2; 0, 2
5 2x 5 0 1
2
x 52; 52 , 0 x-intercept: 0 x
5x 1
20. y 4x2 3 0 2 x
x 4; 4, 0
y-intercept: y 40 3 3; 0, 3
2
26. y x 3x
2
x-intercept: 0 4x2 3
3x 1
2
3 4x2
None. y cannot equal 0. 02 30
y-intercept: y
30 1
2
21. y x2 x 2
y 0; 0, 0
y-intercept: y 02 0 2
y 2; 0, 2 x2 3x
x-intercepts: 0
3x 1
2
x-intercepts: 0 x2 x 2
xx 3
0 x 2x 1 0
3x 1
2
x 2, 1; 2, 0, 1, 0
x 0, 3; 0, 0, 3, 0
22. y2 x3 4x
27. x2 y x2 4 y 0
y-intercept: y 0 40
2 3
y-intercept: 02 y 02 4 y 0
y 0; 0, 0
y 0; 0, 0
x-intercepts: 0 x3 4x
x-intercept: x20 x2 40 0
0 xx 2x 2
x 0; 0, 0
x 0, 2; 0, 0, 2, 0
28. y 2x
23. y x
y-intercept: y 20 02 1
y-intercept: y 0 16 0 2
0; 0, 0
y 1; 0, 1
x-intercepts: 0 x 16 x2
x-intercept: 0 2x x2 1
0 x 4 x4 x 2x x 1
2
x 0, 4, 4; 0, 0, 4, 0, 4, 0
4x2 x2 1
24. y x 1 x2 1 3x2 1
2 x2 1
y-intercept: y 0 1 0 1 3
y 1; 0, 1 x 3
x-intercept: 0 x 1 x2 1 3
3 3
x 1; 1, 0 x ; , 0
3 3
Note: x 3 3 is an extraneous solution.
Preparation for Calculus
Section 1.1 Graphs and Models ............................................................................ 2
Section 1.2 Linear Models and Rates of Change ................................................. 11
Section 1.3 Functions and Their Graphs ............................................................. 22
Section 1.4 Review of Trigonometric Functions ................................................. 36
Section 1.5 Inverse Functions ............................................................................ 45
Section 1.6 Exponential and Logarithmic Functions ........................................... 62
Review Exercises ................................................................................................... 72
Problem Solving .................................................................................................... 87
,C H A P T E R 1
Preparation for Calculus
Section 1.1 Graphs and Models
1. To find the x-intercepts of the graph of an equation, 8. y 5 2x
let y be zero and solve the equation for x. To find the
x 1 0 1 2 5
3 4
y-intercepts of the graph of an equation, let x be zero 2
and solve the equation for y. y 7 5 3 1 0 1 3
2. Symmetry helps in sketching a graph because you need
only half as many points to plot. Answers will vary.
3. y 32 x 3
x-intercept: 2, 0
y-intercept: 0, 3
Matches graph (b).
4. y 9 x2 9. y 4 x2
x-intercepts: 3, 0, 3, 0 x 3 2 0 2 3
y-intercept: 0, 3 y 5 0 4 0 5
Matches graph (d).
5. y 3 x2
x-intercepts:
3, 0 , 3, 0
y-intercept: 0, 3
Matches graph (a).
6. y x3 x
10. y x 3
2
x-intercepts: 0, 0, 1, 0, 1, 0
y-intercept: 0, 0 x 0 1 2 3 4 5 6
Matches graph (c). y 9 4 1 0 1 4 9
7. y 1x
2
2
x 4 2 0 2 4
y 0 1 2 3 4
2
, Section 1.1 Graphs and Mͅ odels 3
11. y x 1 3
15. y
x
x −4 −3 −2 −1 0 1 2
x 3 2 1 0 1 2 3
y 3 2 1 0 1 2 3
y 1 32 3 Undef. 3 3
2
1
12. y x 1
x 3 2 1 0 1 2 3 1
16. y
y 2 1 0 1 0 1 2 x 2
x 6 4 3 2 1 0 2
y 14 12 1 Undef. 1 1
2
1
4
13. y x 6
x 0 1 4 9 16
y 6 5 4 3 2 17. y 5 x
(a) 2, y 2, 1.73 y 52 3 1.73
14. y x 2
(b) x, 3 4, 3 3 5 4
x 2 1 0 2 7 14 18. y x5 5x
y 0 1 2 2 3 4
(a) 0.5, y 0.5, 2.47
(b) x, 4 1.65, 4 and x, 4 1, 4
, 4 Chapter 1 Preparation for Calculus
19. y 2 x 5
25. y 2 x
y-intercept: y 20 5 5; 0, 5 5x 1
2 0
x-intercept: 0 2x 5 y-intercept: y 2; 0, 2
5 2x 5 0 1
2
x 52; 52 , 0 x-intercept: 0 x
5x 1
20. y 4x2 3 0 2 x
x 4; 4, 0
y-intercept: y 40 3 3; 0, 3
2
26. y x 3x
2
x-intercept: 0 4x2 3
3x 1
2
3 4x2
None. y cannot equal 0. 02 30
y-intercept: y
30 1
2
21. y x2 x 2
y 0; 0, 0
y-intercept: y 02 0 2
y 2; 0, 2 x2 3x
x-intercepts: 0
3x 1
2
x-intercepts: 0 x2 x 2
xx 3
0 x 2x 1 0
3x 1
2
x 2, 1; 2, 0, 1, 0
x 0, 3; 0, 0, 3, 0
22. y2 x3 4x
27. x2 y x2 4 y 0
y-intercept: y 0 40
2 3
y-intercept: 02 y 02 4 y 0
y 0; 0, 0
y 0; 0, 0
x-intercepts: 0 x3 4x
x-intercept: x20 x2 40 0
0 xx 2x 2
x 0; 0, 0
x 0, 2; 0, 0, 2, 0
28. y 2x
23. y x
y-intercept: y 20 02 1
y-intercept: y 0 16 0 2
0; 0, 0
y 1; 0, 1
x-intercepts: 0 x 16 x2
x-intercept: 0 2x x2 1
0 x 4 x4 x 2x x 1
2
x 0, 4, 4; 0, 0, 4, 0, 4, 0
4x2 x2 1
24. y x 1 x2 1 3x2 1
2 x2 1
y-intercept: y 0 1 0 1 3
y 1; 0, 1 x 3
x-intercept: 0 x 1 x2 1 3
3 3
x 1; 1, 0 x ; , 0
3 3
Note: x 3 3 is an extraneous solution.