11. 13.
15. 17. 19.
21. a. b.
c. d. none e. max: ( , 4)
f. g.
23. (3, 4), (3, ), 25. 27.
29.
CHAPTER 9
Exercises 9.1, pp. 770–772
1. pattern, order 3. recursive 5. formula defining the sequence uses the
preceding term(s); answers will vary. 7. 1, 3, 5, 7;
9. 0, 9, 24, 45; 11. 2, 4;
13. 15.
17. 1,
19.
21. 4, 16;
23. a. 79 b. { , 2, 7, 14, 23} 25. a. b. {1, }
27. a. b. {2, 1, } 29. a. approx. 2.6 b. {2, }
31. a. b. {}33. 2, 7, 32, 157, 782
35. 4, 19, 364, 132,499 37. 64, 32, 16, 8, 4
39. 336 41. 36 43. 28 45. 47.
49. 1, 2, 51. 15 53. 64 55.
57. 59.
61.
63. 65.
67.
69. a. b. 71. a. b.
73. 75. 77. 79. 35 81. 100
83. 35, verified 85. $7.25, $7.75, $8.25, $8.75, $9.25; $17,760
87. ; 6000, 4800, 3840, 3072, 2457.60, 1966.08
89. 91. approaches 1
93.
95. or 0.25 97.
99.
Exercises 9.2, pp. 779–782
1. common, difference 3. , nth 5. Answers will vary.
7. arithmetic; 9. arithmetic; 11. not arithmetic; all prime
13. arithmetic; 15. not arithmetic; a
n
n
2
d
1
24
d 2.5d 3
n1a
1
a
n
2
2
115, 22, 115, 22, 1 15, 22, 115, 22
3
x
1
81
; x 4
1
4
c
兺
n
j1
a
j
c1a
1
a
2
a
3
p
a
n1
a
n
2
兺
n
j1
ca
j
ca
1
ca
2
ca
3
p
ca
n1
ca
n
⬇2690
a
n
600010.82
n1
兺
7
n3
n
2
n
兺
3
n1
n
2
3
兺
5
n1
1n 32
兺
q
k1
1
k
2
兺
q
k1
12k 12
兺
5
n1
5n
兺
5
n1
4n
1
3
1
8
a
1
15
b
1
24
a
1
35
b
1
48
27
112
6 8 10 12 14 500.5 2 4.5 8 15
1 2 132 4 152 6 1724
1 5 15 29 47 952 1 4 7 10
137
60
9
2
,
32
3
1
3
,
1
120
,
1
15,120
,
1
3,991,680
1
2
,
1
3
,
1
4
,
1
5
1,
1
3
,
1
10
,
1
21
,
1
36
,
1
55
1
36
9
4
,
64
27
,
625
256
,
7776
3125
1
2
,
1
4
,
1
8
1
32
1
2
,
1
3
,
1
4
,
1
5
1
5
1
a
8
256; a
12
40968,2,
1
2
,
1
6
,
1
12
,
1
20
; a
8
1
72
; a
12
1
156
1
2
,
1
3
,
1
4
; a
8
1
8
; a
12
1
12
1
2
,
1
4
,
1
8
,
1
16
; a
8
1
256
; a
12
1
4096
1
2
,
2
3
,
3
4
,
4
5
; a
8
8
9
; a
12
12
13
a
12
12a
8
8;3,1,a
12
429a
8
189;
a
12
23a
8
15;
x ⬇ 1.387 ax
2 ln 2 ln 3
ln 2 ln 3
or
ln 12
ln 6
b
x 6, x 23
1
3
L13, 42, 13, 424
f
1x26 0: x 僆 1q, 42 ´ 12, q2f 1x27 0: x 僆 14, 22
1f
1x2c: x 僆 1q, 12, f 1x2T: x 僆 11, q2
y 僆 1q, 44x 僆 1q, q2
x
y
1010
10
10
(5, 2)
r 3
x
y
1010
10
10
f(x)
(0, 0)
x 1
x
y
x 3
x 3
1010
10
10
h(x)
(2, 0)
(
0, fl
)
x
y
1010
10
10
(3, 1)
x
y
1010
10
10
(0, 5)
(2, 3)
17. arithmetic; 19. 2, 5, 8, 11 21. 7, 5, 3, 1
23. 0.3, 0.33, 0.36, 0.39 25. 2, 3 27.
29.
31.
33.
35.
37. 61 39. 1 41. 2.425 43. 9 45. 43 47. 21 49. 26
51. a. appears linear b. c.
53. a. appears nonlinear b. no common difference
55. 57. 59.
61. 1275
63. 601.25
65.
67. 82.5 69. 74.04 71. 73.
75. at 11
P
.
M
. 77. 5.5 in.; 54.25 in. 79. ; yes
81. a. linear function b. quadratic 83.
85. 1364
Exercises 9.3, pp. 791–795
1. multiplying 3. 5. Answers will vary. 7.
9. 11. not geometric; 13.
15. not geometric; ratio of terms decreases by 1 17.
19. 21. 23. not geometric;
25. 5, 10, 20, 40 27. 3, 29. 4, 413
, 12, 1213
3
2
,
3
4
6,
a
n
240
n!
r
4
x
r
1
2
r
2
5
r 0.1a
n
n
2
1r 2
r 2a
1
r
n1
f 1x2 49x 972;
t ⬇ 3.6
a
7
220; a
12
2520
S
6
21; S
75
285021022
534
d
115
126
, a
1
472
63
a
1
0.65d 0.375,d 3, a
1
1
7
0
7
2
a
n
0.75n 0.75d 0.75
a
6
21
4
, a
10
33
4
, a
12
39
4
a
1
3
2
, d
3
4
, a
n
3
4
n
3
4
,
a
10
6.45, a
12
6.75
a
n
0.15n 4.95, a
6
5.85,
a
1
5.10, d 0.15,
a
6
27, a
10
47, a
12
57a
1
2, d 5, a
n
5n 3,
2, 5, 8, 11
3
4
,
5
8
,
1
2
,
3
8
5
2
,
3
2
,
d
6
Student Answer Appendix SA-45
cob19545_saa_039-051.qxd 12/17/10 9:28 PM Page SA-45