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EXERCISE 0.2 (page 3)
1. True. 3. False; the natural numbers are 1, 2, 3, and so on.5. True. 7. False; =5, a positive integer.9. True. 11. True.
7. Adding 5 to both sides; equivalence guaranteed.9. Raising both sides to the fourth power; equivalence notguaranteed.11. Dividing both sides by x; equivalence not guaranteed.13. Multiplying both sides by x-1; equivalence notguaranteed.15. Multiplying both sides by (x-5)/x; equivalence notguaranteed.
17. . 19. 0. 21. 1. 23. . 25. –1.
27. 2. 29. . 31. 126. 33. 8. 35. .
37. . 39. . 41. . 43. 3. 45. .
47. . 49. . 51. .
53. . 55. 120 m.
57. c=x+0.0825x=1.0825x. 59. 3 years.
61. 31 hours. 63. 0.00001. 65. . 67. .
PRINCIPLES IN PRACTICE 1.2
1. 8 mi/h. 2. .
3. ramp is 5 feet long.
EXERCISE 1.2 (page 46)
1. . 3. �. 5. . 7. 2. 9. 0. 11. .
13. . 15. 3. 17. . 19. �. 21. 11.
23. . 25. . 27. 2. 29. 7. 31. .
33. . 35. . 37. .
39. 20. 41. .
43. Antenna B: 4 m; Antenna A: 12.25 m.
PRINCIPLES IN PRACTICE 1.3
1. The number is –5 or 6. 2. 50 feet by 60 feet.3. 1*1*5. 4. 15 items at $15 per item.5. 2.5 seconds and 7.5 seconds. 6. $100 7. Never.
EXERCISE 1.3 (page 53)
1. 2. 3. 4, 3. 5. 3, –1. 7. 4, 9. 9. —2.
11. 0, 8. 13. . 15. 1, . 17. 5, –2. 19. 0, .
21. 0, 1, –4. 23. 0, —8. 25. 0, . 27. –3, –1, 2.
29. 3, 4. 31. 4, –6. 33. . 35. .
37. No real roots. 39. . 41. 40, –25.
43. . 45. . 47. 2, .
49. . 51. –4, 1. 53. . 55. .
57. 6, –2. 61. 5, –2. 63. . 65. –2. 67. 6.
69. 4, 8. 71. 2. 73. 0, 4. 75. 4. 77. 64.15, 3.35.79. 6 inches by 8 inches. 83. 1 year and 10 years.85. 86.8 cm or 33.2 cm. 87. a. 9 s; b. 3 s or 6 s.89. 1.5, 0.75. 91. No real root. 93. 1.999, 0.963.
REVIEW PROBLEMS—CHAPTER 1 (page 56)
1. . 3. . 5. . 7. �. 9. . 11. .
13. . 15. . 17. 0, . 19. 5. 21. .
23. –3. 25. . 27. —2, —3. 29. .
31. . 33. 9. 35. 5. 37. No solution.
39. 10. 41. 4, 8. 43. –8, 1. 45. Q= .
47. C¿=l2(n-1-C). 49. T=;2� .
51. v=; . 55. .
57. –0.757, 0.384.
6, 54B2mgh - mv2
I
AL
g
EA
4�k
4 ; 1133
12
5 ; 1136
58
,
;
2163
75
-53
, 1-97
13
52
-12
-215
14
32
32
, -1157
, 115
;
155
, ;
12
-12
;13, ;12-2 ; 114
2
12
, -53
7 ; 1372
32
12
, -43
32
-52
12
t =d
r - c; r =
d
t+ c
n =2mI
rB- 1t =
r - d
rd-
94
4936
-
109
2625
513
18
53
83
15
2x2 + 16 - x = 2; x = 3;
t =d
r + w; w =
d
t- r
10r + 2
=6
r - 2;
1461
18
, -1
14
a1 =2S - nan
n
r =S - P
Ptq =
p + 18
P =I
rt
78
143
6017
-
3718
-
269
103
125
52
103
AS
πr =
d
t
1312x - 15x2 - 5
216-16 + 213
313
21x - 21x + h1x1x + h
1x + 2 2 16x - 1 22x2 1x + 3 2
4x + 13x
x
1 - xy
x2 + 2x + 1x2
35 - 8x
1x - 1 2 1x + 5 22x - 3
1x - 2 2 1x + 1 2 1x - 1 2
2x2 + 3x + 1212x - 1 2 1x + 3 2
11 - p2
73t
-12x + 3 2 11 + x 2
x + 4
2x2
x - 1
AN2 Answers to Odd-Numbered Problems �
� Answers to Odd-Numbered Problems AN3
MATHEMATICAL SNAPSHOT—CHAPTER 1 (page 58)
1. a. $107.15; b. $10.26; c. 10 lb; d. 10.44 lb; e. 4.4%3. –1.9%.
EXERCISE 2.1 (page 66)
1. 120. 3. 48 of A, 80 of B. 5. . 7. 1 m.
9. 13,000. 11. $4000 at 6%, $16,000 at .
13. $4.25. 15. 4%. 17. 80. 19. $8000.21. 1138. 23. $116.25. 25. 40. 27. 46,000.29. Either $440 or $460. 31. $100. 33. 77.35. 80 ft by 140 ft. 37. 9 cm long, 4 cm wide.39. $112,000. 41. 60. 43. Either 125 units of A and100 units of B, or 150 units of A and 125 units of B.
1. 120,001. 3. 17,000. 5. 60,000. 7. $25,714.29.9. 1000. 11. t>36.5. 13. At least $67,400.
PRINCIPLES IN PRACTICE 2.4
1. |w-22 oz| � 0.3 oz.
EXERCISE 2.4 (page 82)
1. 13. 3. 6. 5. 5. 7. –4<x<4.9. . 11. a. |x-7|<3; b. |x-2|<3;c. |x-7| � 5; d. |x-7|=4; e. |x+4|<2;f. |x|<3; g. |x|>6; h. |x-6|>4; i. |x-105|<3;j. |x-850|<100. 13. |p1-p2| � 8. 15. —7.
17. —6. 19. 13, –3. 21. . 23. .
25. (–4, 4). 27. (–q ,–8) ´ (8, q). 29. (–9, –5).
31. (–q, 0) ´ (1, q). 33. .
35. (–q, 0] ´ . 37. |d-17.2| � 0.03 m
39. (–q, Â-hÍ) ´ (Â+hÍ, q).
REVIEW PROBLEMS—CHAPTER 2 (page 84)
1. (–q, 0]. 3. . 5. �. 7. .
9. (–q, q). 11. –2, 5. 13. .
15. ´ . 17. 542. 19. 6000.
21. c<$212,814.
MATHEMATICAL SNAPSHOT—CHAPTER 2 (page 85)
1. 1 hour. 3. 1 hour. 5. 600; 310.
PRINCIPLES IN PRACTICE 3.1
1. a. a(r)=�r2; b. all real numbers; c. r � 0.
2. a. t(r)= ; b. all real numbers except 0; c. r>0;
d. ;
e. The time is scaled by a factor c; .
3. a. 300 pizzas; b. $21.00 per pizza; c. $16.00 per pizza.
EXERCISE 3.1 (page 93)
1. All real numbers except 0. 3. All real numbers � 3.
27. a. x2+2hx+h2+2x+2h; b. 2x+h+2.29. a. 2-4x-4h-3x2-6hx-3h2;
b. –4-6x-3h. 31. a. ; b. .
33. 9. 35. y is a function of x; x is a function of y.37. y is a function of x; x is not a function of y.39. Yes. 41. V=f(t)=20,000+800t.43. Yes; P; q. 45. 400 pounds per week; 1000 poundsper week; amount supplied increases as the price increases.47. a. 4; b. 8 ; c. f(2I0)=2 f(I0); doubling the intensity increases the response by a factor of 2 .49. a. 3000, 2900, 2300, 2000; 12, 10;b. 10, 12, 17, 20; 3000, 2300. 51. a. –5.13; b. 2.64;c. –17.43. 53. a. 11.33; b. 50.62; c. 2.29.
PRINCIPLES IN PRACTICE 3.2
1. a. p(n)=$125; b. The premiums do not change;c. constant function.2. a. quadratic function; b. 2; c. 3.
3. 4. 7!=5040.
EXERCISE 3.2 (page 98)
1. Yes. 3. No. 5. Yes. 7. No.9. All real numbers. 11. All real numbers.13. a. 3; b. 7. 15. a. 4; b. –3. 17. 8, 8, 8.19. 1, –1, 0, –1. 21. 8, 3, 1, 1. 23. 720. 25. 2.27. 5. 29. c(i)=$4.50; constant function.31. a. C=850+3q; b. 250.
33. 35. .
37. a. All T such that 30 � T � 39; b. 4, .
39. a. 237,077.34; b. –434.97; c. 52.19.41. a. 2.21; b. 9.98; c. –14.52.
PRINCIPLES IN PRACTICE 3.3
1. c(s(x))=c(x+3)=2(x+3)=2x+6.2. Let the length of a side be represented by the function l(x)=x+3 and the area of a square with sides of length x be represented by a(x)=x2. Then g(x)=(x+3)2=[l(x)]2=a(l(x)).
EXERCISE 3.3 (page 103)
1. a. 2x+8; b. 8; c. –2; d. x2+8x+15; e. 3;
f. ; g. x+8; h. 11; i. x+8. 3. a. 2x2+x;
b. –x; c. ; d. x4+x3; e. (for x ≠ 0);
f. –1; g. (x2+x)2=x4+2x3+x2; h. x4+x2; i. 90.
5. 6; –32. 7. .
9. . 11. f(x)=x5, g(x)=4x-3.
13. f(x)= , g(x)=x2-2.
15. f(x)= , g(x)= .
17. a. r(x)=9.75x; b. e(x)=4.25x+4500;c. (r-e)(x)=5.5x-4500.19. 400m-10m2; the total revenue received when the total output of m employees is sold.21. a. 14.05; b. 1169.64. 23. a. 345.03; b. –1.94.
PRINCIPLES IN PRACTICE 3.4
1. y=–600x+7250; x-intercept ;
y-intercept (0, 7250).2. y=24.95; horizontal line; no x-intercept;y-intercept (0, 24.95).3.
4.
EXERCISE 3.4 (page 112)
1.
3. a. 1, 2, 3, 0; b. all real numbers; c. all real numbers;d. –2. 5. a. 0, –1, –1; b. all real numbers;c. all nonpositive real numbers; d. 0.
x
y
(– , –2)12
(0, 0)
Q.I
Q.III Q.IV
(2, 7)
(8, –3)
–1–3
8
7
xtherms
y
80604020 100
20
40
60
Cos
t (do
llars
)
(0, 0)
(70, 37.1)
(100, 59.3)
xhours
y
4321 5
12
24
36M
iles
(0, 0)
(5, 0)
(2.5, 30)
a121
12, 0b
x + 13
51x
1x
1v + 3
; B2w2 + 3w2 + 1
41 t - 1 2 2 +
14t - 1
+ 1; 2
t2 + 7t
x2
x2 + x=
x
x + 112
x + 3x + 5
174
, 334
964
c 1n 2 = e8.50n
8.00n
ifif
n 6 10,n � 10.
c 1n 2 = •3.50n
3.00n
2.75n
ififif
n � 5,5 6 n � 10,n 7 10.
312
312312
-
1x 1x + h 2
1x + h
116
AN4 Answers to Odd-Numbered Problems �
� Answers to Odd-Numbered Problems AN5
7. (0, 0); function; all real numbers; all real numbers.
9. (0, –5), ; function; all real numbers;
all real numbers.
11. (0, 0); function; all real numbers;all nonnegative real numbers.
13. Every point on y-axis; not a function of x.
15. (0, 0); function; all real numbers; all real numbers.
17. (0, 0); not a function of x.
19. (0, 2), (1, 0); function; all real numbers; all real numbers.
21. All real numbers; all real numbers � 4;(0, 4), (2, 0), (–2, 0).
23. All real numbers; 2; (0, 2).
25. All real numbers; all real numbers � –3; (0, 1), (2_ , 0).
x
y
2 +(2, –3)
3
2 – 3
1
13
x
y
2
t
s
2–2
4
x
y
2
1
x
y
x
y
x
y
x
y
x
y
5
–5
3
a53
, 0b
x
y
27. All real numbers; all real numbers; (0, 0).
29. All real numbers � 5; all nonnegative real numbers;(5, 0).
31. All real numbers; all nonnegative real numbers;
(0, 1), .
33. All nonzero real numbers; all positive real numbers;no intercepts.
35. All nonnegative real numbers; all real numbers cwhere 0 � c<6.
37. All real numbers; all nonnegative real numbers.
39. (a), (b), (d).41.
43. As price decreases, quantity increases; p is a function of q.
45.
47. –1, –0.35. 49. 0.62, 1.73, 4.65. 51. –0.84, 2.61.53. –0.49, 0.52, 1.25. 55. a. 3.94; b. –1.94.57. a. (–q, q); b. (–1.73, 0), (0, 4.00).59. a. 2.07; b. [2.07, q); c. (0, 2.39); d. no.
EXERCISE 3.5 (page 119)
1. (0, 0); sym. about origin.3. (—2, 0), (0, 8); sym. about y-axis.5. (—2, 0); sym. about x-axis, y-axis, origin.7. (–2, 0); sym. about x-axis. 9. Sym. about x-axis.11. (–21, 0), (0, –7), (0, 3).
13. (0, 0); sym. about origin. 15. .a0, 38b
x
y
4 5 12
4
q
p
5 25
20
5
x
y
20
16
12
8
4
10P.M.
86421210A.M.
Cos
t (do
llars
)
x
g (x )
3
9
p
c
6
65
t
F(t )
x
f (x )
1
1
2
a12
, 0b
r
s
5
t
f (t )
AN6 Answers to Odd-Numbered Problems �
� Answers to Odd-Numbered Problems AN7
17. (2, 0), (0, —2); sym. about x-axis.
19. (—2, 0), (0, 0); sym. about origin.
21. (0, 0); sym. about x-axis, y-axis, origin.
23. (—2, 0), (0, —4); sym. about x-axis, y-axis, origin.
25. a. (—1.18, 0), (0, 2); b. 2; c. (–q, 2].
EXERCISE 3.6 (page 122)
1.
3.
5.
7.
9.
11.
13. Translate 4 units to the right and 3 units upward.15. Reflect about the y-axis and translate 5 units downward.
REVIEW PROBLEMS—CHAPTER 3 (page 123)
1. All real numbers except 1 and 2. 3. All real numbers.5. All nonnegative real numbers except 1.7. 7, 46, 62, 3t2-4t+7. 9. 0, 2, .
11. . 13. –8, 4, 4, –92.35
, 0, 1x + 4
x, 1u
u - 4
1t, 2x3 - 1
x
y
f (x) = xy = –x
x
y
1
1
y = 1 – (x – 1)2
f (x ) = x 2
x
y
–1
–2
f (x ) = x
y = x + 1 –2
x
y
1–1
1
2
–1
–2 y = 23x
f (x ) = 1x
x
y
f (x ) =
2
y = 1x – 2
1x
x
y
–2
y = x 2 – 2
f (x ) = x 2
x
y
–2
–4
4
2
x
y
x
y
2–2
x
y
2
2
–2
15. a. 3-7x-7h; b. –7.17. a. 4x2+8hx+4h2+2x+2h-5;b. 8x+4h+2. 19. a. 5x+2; b. 22; c. x-4;
d. 6x2+7x-3; e. 10; f. ;
g. 3(2x+3)-1=6x+8; h. 38;i. 2(3x-1)+3=6x+1.
21. . 23. , (x+2)3/¤.
25. (0, 0), (— , 0); sym. about origin.27. (0, 9), (—3, 0); sym. about y-axis.
29. (0, 2), (–4, 0); all u � –4; all real numbers � 0.
31. ; all t Z 4; all positive real numbers.
33. All real numbers; all real numbers � 1.
35.
37. a, c. 39. –0.67, 0.34, 1.73.41. –1.50, –0.88, –0.11, 1.09, 1.40.43. a. (–q, q); b. (1.92, 0), (0, 7)45. a. None; b. 1, 3.
MATHEMATICAL SNAPSHOT—CHAPTER 3 (page 125)
1. $28,321. 3. $87,507.90. 5. Answers may vary.
PRINCIPLES IN PRACTICE 4.1
1. –2000; the car depreciated $2000 per year.
2. S=14T+8. 3. .
4. slope= ; y-intercept= .
5. 9C-5F+160=0.6.
7. The slope of is 0; the slope of is 7; the slope ofis 1. None of the slopes are negative reciprocals of each
other, so the triangle does not have a right angle. The pointsdo not define a right triangle.
63. –2; the stock price dropped an average of $2 per year.65. y=3x+5. 67. slope≠0.65; y-intercept ≠4.38
69. a. y= ; b. y=3x- .
71. y=–x+3300; without modification, the approach angle will cause the plane to crash 700 feet short of the airport. 73. R=50,000T+80,000.75. The lines are parallel. This is expected because theyeach have a slope of 1.5.
PRINCIPLES IN PRACTICE 4.2
1. x=number of skis produced; y=number of bootsproduced; 8x+14y=1000.
2. p= .
3. Answers may vary, but two possible points are (0, 60) and (2, 140).
numbers.25. 420 gal of 20% solution, 280 gal of 30% solution.27. 0.5 lb of cotton; 0.25 lb of polyester; 0.25 lb of nylon.29. 275 mi/h (speed of airplane in still air),25 mi/h (speed of wind).31. 240 units (Early American), 200 units (Contemporary).33. 800 calculators from Exton plant, 700 from Whyton plant.35. 4% on first $100,000, 6% on remainder.37. 60 units of Argon I, 40 units of Argon II.39. 100 chairs, 100 rockers, 200 chaise lounges.41. 40 semiskilled workers, 20 skilled workers, 10 shippingclerks. 45. x=3, y=2. 47. x=8.3, y=14.0.
11. Cannot break even at any level of production.13. 15 units or 45 units. 15. a. $12; b. $12.18.17. 5840 units; 840 units; 1840 units. 19. $4.21. Total cost always exceeds total revenue—no break-evenpoint. 23. Decreases by $0.70.25. pA=5; pB=10. 27. 2.4 and 11.3.
REVIEW PROBLEMS—CHAPTER 4 (page 176)
1. 9. 3. y=–x+1; x+y-1=0.
5. y= -1; x-2y-2=0. 7. y=4; y-4=0.
9. y= +2; x-3y+6=0.
11. Perpendicular. 13. Neither. 15. Parallel.
17. y= . 19. y= .
21. –2; (0, 4).
23. (3, 0), (–3, 0), (0, 9); (0, 9).
25. (5, 0), (–1, 0), (0, –5); (2, –9).
27. 3; (0, 0).
t
p
t
y
2 5–1
–9
–5
x
y
3–3
9
x
y
2
4
43
; 032
x - 2; 32
13
x
12
x
q
yTR
TC
2000 6000
15,000(4500, 13,500)
5000
q
p
100 200
10
(100, 5)5
-114114117117
x =32
- r +12
s, y = r, z = s;
x = -13
r, y =53
r, z = r
x =12
, y =12
, z =14
32
29. (0, –3); (–1, –2).
31. . 33. x=2, y=–1.
35. x=8, y=4. 37. x=0, y=1, z=0.39. x=–3, y=–4; x=2, y=1.41. x=–2-2r, y=7+r, z=r; r is any real number.43. x=r, y=r, z=0; r is any real number.
45. a+b-3=0; 0. 47. f(x)= .
49. 50 units; $5000. 51. 6. 53. 1250 units; $20,000.55. 2.36 tons per square km. 57. x=230, y=–130.59. x=0.75, y=1.43.
MATHEMATICAL SNAPSHOT—CHAPTER 4 (page 170)
1. Advantage I is the best plan for airtimes from 85 to
153 minutes. Advantage II is the best plan for airtimes
from 153 to 233 minutes.
3. If the initial guess is on the horizontal portion of both graphs, the calculator may not be able to find the intersection point.
PRINCIPLES IN PRACTICE 5.1
1. The shape of the graphs are the same. The value of Ascales the ordinate of any point by A.2.
1.1; The investment increases by 10% every year(1+1(0.1)=1+0.1=1.1).
Between 7 and 8 years.
3.
0.85; The car depreciates by 15% every year (1-1(0.15)=1-0.15=0.85).
Between 4 and 5 years.4. y=1.08 ; Shift the graph 3 units to the right.5. $3684.87; $1684.87. 6. $2753.79; $753.79.7. 117 employees.8.
EXERCISE 5.1 (page 192)
1. 3.
5. 7.
x
y
–21
9
x
y
1–1
8
2
x
y
1–1
3
1
x
y
1
4
1
tyears
P
10 20
1
t - 3
xyears
y
4321 5
1
2
Year Multiplicative ExpressionDecrease
0 1 0.850
1 0.85 0.851
2 0.72 0.852
3 0.61 0.853
xyears
y
4321 5
1
2
Year Multiplicative ExpressionIncrease
0 1 1.10
1 1.1 1.11
2 1.21 1.12
3 1.33 1.13
4 1.46 1.14
13
13
13
-43
x +193
x =177
, y = -87
x
y
–1 – 2– 3
AN12 Answers to Odd-Numbered Problems �
� Answers to Odd-Numbered Problems AN13
9. 11.
13. B. 15. 138,750. 17. .
19. a. $6014.52; b. $2014.52.21. a. $1964.76; b. $1264.76.23. a. $14,124.86; b. $10,124.86.25. a. $6256.36; b. $1256.36.27. a. $9649.69; b. $1649.69.29. $10,446.15.31. a. N=400(1.05)t; b. 420; c. 486.33.
1.3; The recycling increases by 30% every year(1+1(0.3)=1+0.3=1.3).
Between 4 and 5 years.35. 97,030. 37. 4.4817. 39. 0.4966.41. 43. 0.2240.
45. (ek)t, where b=ek.47. a. 10; b. 7.6;
c. 2.5; d. 25 hours.49. 32 years.51. 0.1465.55. 3.17.57. 4.2 min.59. 16.
PRINCIPLES IN PRACTICE 5.2
1. t=log2 16; t=the number of times the bacteria have
67. a. $180,000, $520,000, $400,000, $270,000, $380,000,$640,000; b. $390,000, $100,000, $800,000; c. $2,390,000;
d. . 71. .
73. .
PRINCIPLES IN PRACTICE 6.4
1. 5 blocks of A, 2 blocks of B, and 1 block of C.2. 3 of X; 4 of Y; 2 of Z. 3. A=3D; B=1000-2D; C=500-D; D=any amount (� 500).
c 15.606-739.428
64.08373.056
dc72.8251.32
-9.8-36.32
d110239
, 129239
£430
-103
3-1
2§ £
r
s
t
§ = £97
15§
c37
1-2d cx
yd = c6
5d .
c 6-7
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EXERCISE 6.4 (page 261)
1. Not reduced. 3. Reduced. 5. Not reduced.
7. . 9. . 11. .
13. x=2, y=1. 15. No solution.
17. x= where r is any
real number. 19. No solution.21. x=–3, y=2, z=0. 23. x=2, y=–5, z=–1.25. x1=0, x2=–r, x3=–r, x4=–r, x5=r, where r is any real number. 27. Federal, $72,000; state, $24,000.29. A, 2000; B, 4000; C, 5000. 31. a. 3 of X, 4 of Z;2 of X, 1 of Y, 5 of Z; 1 of X; 2 of Y, 6 of Z; 3 of Y, 7 of Z;b. 3 of X, 4 of Z; c. 3 of X, 4 of Z; 3 of Y, 7 of Z.33. a. Let s, d, g represent the numbers of units S, D, G respectively. The six combinations are given by:
b. The combination s=0, d=3, g=5.
PRINCIPLES IN PRACTICE 6.5
1. Infinitely many solutions:
in parametric form: where r is
any real number.
EXERCISE 6.5 (page 267)
1. w=–r-3s+2, x=–2r+s-3, y=r, z=s(where r and s are any real numbers).3. w=–s, x=–3r-4s+2, y=r, z=s(where r and s are any real numbers).5. w=–2r+s-2, x=–r+4, y=r, z=s(where r and s are any real numbers).7. x1=–2r+s-2t+1, x2=–r-2s+t+4, x3=r, x4=s, x5=t (where r, s, and t are any real numbers).9. Infinitely many. 11. Trivial solution.13. Infinitely many. 15. x=0, y=0.
17. . 19. x=0, y=0.
21. x=r, y=–2r, z=r.23. w=–2r, x=–3r, y=r, z=r.
PRINCIPLES IN PRACTICE 6.6
1. Yes. 2. MEET AT NOON FRIDAY.
3. E–1= ; F is not invertible.
4. A: 5000 shares; B: 2500 shares; C:2500 shares
EXERCISE 6.6 (page 275)
1. 3. Not invertible. 5. .
7. Not invertible. 9. Not invertible (not a square matrix).
43. a. Let x, y, z represent the weekly doses of capsules ofbrands I, II, III, respectively. The combinations are given by:
b. Combination 4:x=1, y=0, z=3.
45. 47.
MATHEMATICAL SNAPSHOT—CHAPTER 6 (page 298)
1. $151.40. 3. It is not possible, because guests 3 and 4 each cost the lodge the same amount per day.
PRINCIPLES IN PRACTICE 7.1
1. 2x+1.5y>0.9x+0.7y+50, y>–1.375x+62.5;sketch the dashed line y=–1.375x+62.5 and shade thehalf plane above the line. In order to produce a profit, thenumber of magnets of types A and B produced and soldmust be an ordered pair in the region.
2. x � 0, y � 0, x+y � 50, x � 2y; The region consists ofpoints on or above the x-axis and on or to the right of the y-axis. In addition, the points must be on or above the linex+y=50 and on or below the line x=2y.
1. P=640 when x=40, y=20.3. Z=–10 when x=2, y=3.5. No optimum solution (empty feasible region).7. Z=3 when x=0, y=1.
9. C=2.4 when
11. No optimum solution (unbounded).13. 15 widgets, 25 wadgits; $210.15. 4 units of food A, 4 units of food B; $8.17. 10 tons of ore I, 10 tons of ore II; $1100.19. 6 chambers of type A and 10 chambers of type B.21. c. x=y=75.23. Z=15.54 when x=2.56, y=6.74.25. Z=–75.98 when x=9.48, y=16.67.
PRINCIPLES IN PRACTICE 7.3
1. Ship 10t+15 TV sets from C to A, –10t+30 TV setsfrom C to B, –10t+10 TV sets from D to A, and 10t TVsets from D to B, for 0 � t � 1; minimum cost $780.
EXERCISE 7.3 (page 318)
1. Z=33 when x=(1-t)(2)+5t=2+3t,y=(1-t)(3)+2t=3-t, and 0 � t � 1.3. Z=72 when x=(1-t)(3)+4t=3+t,y=(1-t)(2)+0t=2-2t, and 0 � t � 1.
PRINCIPLES IN PRACTICE 7.4
1. 0 gadgets of Type 1, 72 gadgets of Type 2, 12 gadgets ofType 3; maximum profit of $20,400.
EXERCISE 7.4 (page 330)
1. Z=8 when x1=0, x2=4.3. Z=14 when x1=1, x2=5.5. Z=28 when x1=3, x2=2.7. Z=20 when x1=0, x2=5, x3=0.
9. Z=2 when x1=1, x2=0, x3=0.
11. when x1= , x2=
13. W=13 when x1=1, x2=0, x3=3.15. Z=600 when x1=4, x2=1, x3=4, x4=0.17. 0 from A, 2400 from B; $1200.19. 0 chairs, 300 rockers, 100 chaise lounges; $10,800.
PRINCIPLES IN PRACTICE 7.5
1. 35-7t of device 1, 6t of device 2, 0 of device 3, for 0 � t � 1.
EXERCISE 7.5 (page 337)
1. Yes; for the tableau, x2 is the entering variable and the
quotients and tie for being the smallest.
3. No optimum solution (unbounded).5. Z=12 when x1=4+t, x2=t, and 0 � t � 1.7. No optimum solution (unbounded).
9. Z=13 when x1= x2=6t, x3=4-3t, and
0 � t � 1.11. $15,200. If x1, x2, x3 denote the number of chairs,rockers, and chaise lounges produced, respectively, then x1=100-100t, x2=100+150t, x3=200-50t, and 0 � t � 1.
1. Z=7 when x1=1, x2=5.3. Z=4 when x1=1, x2=2, x3=0.
5. Z= when x1= , x2= , x3=0.
7. Z=–17 when x1=3, x2=2.9. No optimum solution (empty feasible region).11. Z=2 when x1=6, x2=10.13. 255 Standard bookcases, 0 Executive bookcases.15. 30% in A, 0% in AA, 70% in AAA; 6.6%.
EXERCISE 7.7 (page 352)
1. Z=54 when x1=2, x2=8.3. Z=216 when x1=18, x2=0, x3=0.5. Z=4 when x1=0, x2=0, x3=4.7. Z=0 when x1=3, x2=0, x3=1.9. Z=28 when x1=3, x2=0, x3=5.11. Install device A on kilns producing 700,000 barrels annually, and device B on kilns producing 2,600,000 barrelsannually. 13. To Exton, 5 from A and 10 from B; toWhyton, 15 from A; $380. 15. a. Column 3: 1, 3, 3;column 4: 0, 4, 8; b. x1=10, x2=0, x3=20, x4=0;c. 90 in.
11. Z=26 when x1=6, x2=1.13. Z=14 when x1=1, x2=2.15. $250 on newspaper advertising, $1400 on radio advertising; $1650.17. 20 shipping clerk apprentices, 40 shipping clerks,90 semiskilled workers, 0 skilled workers; $1200.
REVIEW PROBLEMS—CHAPTER 7 (page 362)
1. 3.
5. 7.
9. 11. Z=3 when x=3, y=0.13. Z=–2 when x=0, y=2.15. No optimum solution
(empty feasible region).17. Z=36 when x=2+2t,
y=3-3t, and 0 � t � 1.19. Z=32 when x1=8, x2=0.21. Z=2 when x1=0, x2=0,
x3=2.
23. Z=24 when x1=0, x2=12.
25. Z= when x1= , x2=0, x3= .
27. No optimum solution (unbounded).29. Z=70 when x1=35, x2=0, x3=0.31. 0 units of X, 6 units of Y, 14 units of Z; $398.33. 500,000 gal from A to D, 100,000 gal from A to C,400,000 gal from B to C; $19,000.35. 10 kg of food A only.37. Z=117.88 when x=7.23, y=3.40.
MATHEMATICAL SNAPSHOT—CHAPTER 7 (page 365)
1. 2 minutes of radiation. 3. Answers may vary.
PRINCIPLES IN PRACTICE 8.1
1. 4.9%. 2. 7 years, 16 days. 3. 7.7208%.4. The $10,000 investment is slightly better over 20 years.
EXERCISE 8.1 (page 372)
1. a. $11,105.58; b. $5105.58. 3. 4.060%. 5. 4.081%.7. a. 10%; b. 10.25%; c. 10.381%; d. 10.471%; e. 10.516%.9. 8.08%. 11. 9.0 years. 13. $10,282.95.15. $38,503.23. 17. a. 18%; b. $19.56%.19. $3198.54. 21. 8% compounded annually.23. a. 5.47%; b. 5.39%. 25. 11.61%. 27. 6.29%.
21. 720. 23. 1680. 25. 252. 27. 756,756.29. a. 90; b. 330. 31. 17,325. 33. a. 1; b. 1; c. 18.35. 3744. 37. 5,250,960.
PRINCIPLES IN PRACTICE 9.3
1. 10,586,800.
EXERCISE 9.3 (page 421)
1. {9D, 9H, 9C, 9S}.3. {1H, 1T, 2H, 2T, 3H, 3T, 4H, 4T, 5H, 5T, 6H, 6T}.5. {mo, mu, ms, me, om, ou, os, oe, um, uo, us, ue, sm, so, sn,se, em, eo, eu, es}.7. a. {RR, RW, RB, WR, WW, WB, BR, BW, BB};b. {RW, RB, WR, WB, BR, BW}.9. Sample space consists of ordered sets of six elements andeach element is H or T; 64.11. Sample space consists of ordered pairs where first ele-ment indicates card drawn and second element indicatesnumber on die; 312.13. Sample space consists of combinations of 52 cardstaken 13 at a time; 52C13.15. {1, 3, 5, 7, 9}. 17. {7, 9}. 19. {1, 2, 4, 6, 8, 10}.21. S. 23. E1 and E4, E2 and E3, E3 and E4.25. E and H, G and H, H and I.27. a. {HHH, HHT, HTH, HTT, THH, THT, TTH, TTT};b. {HHH, HHT, HTH, HTT, THH, THT, TTH};c. {HHT, HTH, HTT, THH, THT, TTH, TTT}; d. S;e. {HHT, HTH, HTT, THH, THT, TTH}; f. �;g. {HHH, TTT}.29. a. {ABC, ACB, BAC, BCA, CAB, CBA};b. {ABC, ACB}; c. {BAC, BCA, CAB, CBA}.
EXERCISE 9.4 (page 433)
1. 600. 3. a. 0.8; b. 0.4. 5. No.
7. a. b. c. d. e. f. g.
9. a. b. c. d. e. f. g. h. i. 0.
11. a. b. c. d.
13. a. b.
15. a. b. c. d. 17. a. b.
19. a. 0.1; b. 0.35; c. 0.7; d. 0.95; e. 0.1, 0.35, 0.7, 0.95.
21. 23. a. b.
25.
27. a. ≠0.040; b. ≠0.026.
29. 31. a. 0.51; b. 0.44; c. 0.03. 33. 4:1.
35. 3:7. 37. 39. 41. 3:1.
EXERCISE 9.5 (page 447)
1. a. b. c. d. e. 3. 1. 5. 0.43.
7. a. b. 9. a. b. c. d.
11. a. b. c. d. e. f.
13. a. b. 15. 17. a. b. 19.
21. 23. 25. 27. 29.
31. 33. 35. 37. a. b.
39. a. b. 41. 43. 45.
47. 0.049. 49. a. 0.06; b. 0.155. 51.
EXERCISE 9.6 (page 458)
1. a. b. c. d. e. f. g. 3.
5. Independent. 7. Independent. 9. Dependent.11. Dependent. 13. a. Dependent; b. dependent;
c. dependent; d. no. 15. Dependent. 17.
19. 21. 23. a. b. c.
25. a. b. c. d. e. 27. a. b.
29. 31. 33. a. b.
35. a. b. c. 37. 0.0106.
EXERCISE 9.7 (page 468)
1. P(E | D)= P(F | D¿)= . 3. ≠0.387.
5. a. ≠0.275; b. ≠0.005. 7. 9.
11. ≠0.910. 13. ≠55.1%. 15. .
17. ≠0.828. 19. 21. ≠0.933.
23. a. =0.205; b. ≠0.585; c. =0.115.
25. a. 0.18; b. 0.23; c. 0.59; d. high quality.
27. ≠0.78.79
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� Answers to Odd-Numbered Problems AN21
REVIEW PROBLEMS—CHAPTER 9 (page 473)
1. 336. 3. 36. 5. 608,400. 7. 32. 9. 210.11. 126. 13. a. 2024; b. 253. 15. 34,650. 17. 560.19. a. {1, 2, 3, 4, 5, 6, 7}; b. {4, 5, 6}; c. {4, 5, 6, 7, 8}; d. �;e. {4, 5, 6, 7, 8}; f. no.21. a. {R1R2R3, R1R2G3, R1G2R3, R1G2G3, G1R2R3,G1R2G3, G1G2R3, G1G2G3}; b. {R1R2G3, R1G2R3, G1R2R3};c. {R1R2R3, G1G2G3}.
23. 0.2. 25. 27. a. b.
29. a. b. 31. 3:5. 33. 35.
37. 0.42. 39. a. b. 41.
43. a. b. independent. 45. Dependent.
47. a. 0.0081; b. 0.2646; c. 0.3483.
49. 51. 53. a. 0.014; b. ≠0.57.
MATHEMATICAL SNAPSHOT—CHAPTER 9 (page 477)
1. ≠0.645.
EXERCISE 10.1 (page 486)
1. Â=1.7; Var(X)=1.01; Í≠1.00.
3. Â= =2.25; Var(X)= =0.6875; Í≠0.83.
5. a. 0.1; b. 5; c. 3.
7. E(X)= =1.5; Í2= =0.75; Í≠0.87.
9. E(X)= =1.2; Í2= =0.36; Í= =0.6.
11. f(0)= , f(1)= , f(2)= .
13. a. –$0.15 (a loss); b. –$0.30 (a loss). 15. $101.43.17. $3.00. 19. $410. 21. Loss of $0.25; $1.
b. 59.18% in compartment 1, 40.82% in compartment 2;c. 60% in compartment 1, 40% in compartment 2.
41. a. ; b. .
REVIEW PROBLEMS—CHAPTER 10 (page 506)
1. Â=1.5, Var(X)=0.65, Í=0.81.
3. a.
= b. 4. 5. $0.10 (a loss).
7. a. $176; b. $704,000.9.
Â=0.3; Í= ≠0.52. 11. . 13. .
15. . 17. a=0.3, b=0.2, c=0.5.
19. X1= , X2= .
21. a. T2= T3= ; b. ;
c. . 23. .
25. a. 76%; b. 74.4% Japanese, 25.6% non-Japanese;c. 75% Japanese, 25% non-Japanese.
MATHEMATICAL SNAPSHOT—CHAPTER 10 (page 508)
1. 7.
3. Against Always Defect: ;
Against Always Cooperate: ;
Against regular Tit-for-tat: .
PRINCIPLES IN PRACTICE 11.1
1. The limit as x S a does not exist if a is an integer, but itexists if a is any other value.
2. 36∏ cc. 3. 3616. 4. 20. 5. 2.
EXERCISE 11.1 (page 521)
1. a. 1; b. 0; c. 1. 3. a. 1; b. does not exist; c. 3.5. f(0.9)=2.8, f(0.99)=2.98, f(0.999)=2.998,f(1.001)=3.002, f(1.01)=3.02, f(1.1)=3.2; 3.7. f(–0.1)≠0.9516, f(–0.01)≠0.9950,f(–0.001)≠0.9995, f(0.001)≠1.0005, f(0.01)≠1.0050.f(0.1)≠1.0517; 1.
9. 16. 11. 20. 13. –1. 15. . 17. 0.
19. 5. 21. –2. 23. 3. 25. 0. 27. .
29. . 31. . 33. 4. 35. 2x. 37. –1.
39. 2x. 41. 2x-3. 43. . 45. a. 1; b. 0.
47. 11.00. 49. –7.00. 51. Does not exist.
PRINCIPLES IN PRACTICE 11.2
1. p(x)=0. The graph starts out high and quickly goes
down toward zero. Accordingly, consumers are willing to purchase large quantities of the product at prices closeto 0.
2. y(x)=500. The greatest yearly sales they can
expect with unlimited advertising is $500,000.3. C(x)= . This means that the cost continues to
increase without bound as more units are made.4. The limit does not exist; $250.
EXERCISE 11.2 (page 531)
1. a. 2; b. 3; c. does not exist; d. –q; e. q; f. q; g. q;h. 0; i. 1; j. 1; k. 1. 3. 1. 5. –q. 7. –q.9. q. 11. 0. 13. Does not exist. 15. 0.17. q. 19. 0. 21. 1. 23. 0. 25. q.
27. 0. 29. . 31. –q. 33. . 35. –q.25
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� Answers to Odd-Numbered Problems AN23
37. . 39. . 41. q. 43. q. 45. q.
47. Does not exist. 49. –q. 51. 0. 53. 1.55. a. 1; b. 2; c. does not exist; d. 1; e. 2.57. a. 0; b. 0; c. 0; d. –q; e. –q.59. 61. 20,000. 63. 20.
65. 1, 0.5, 0.525, 0.631, 0.912, 0.986, 0.998; conclude limit is 1.67. 0. 69. a. 11; b. 9; c. does not exist.
EXERCISE 11.3 (page 535)
1. $5563.87; $1563.87. 3. $1456.87. 5. 4.08%.7. 3.05%. 9. $109.42. 11. $778,800.78.13. a. $21,911; b. $6599. 15. $4.88%.17. $1264. 19. 16 years.21. Option (a): $1072.51; Option (b): $1093.30;Option (c): $1072.18.23. a. $9458.51; b. This strategy is better by $26.90.
EXERCISE 11.4 (page 543)
7. Continuous at –2 and 0. 9. Discontinuous at —3.11. Continuous at 2 and 0. 13. f is a polynomial function.15. f is a rational function and the denominator is never zero.17. None. 19. x=–4. 21. None.23. x=–5, 3. 25. x=0, —1. 27. None.29. x=0. 31. None. 33. x=2.35. Discontinuities at t=1, 2, 3, 4.
1. 17%.3. An exponential model assumes a fixed repayment rate.
PRINCIPLES IN PRACTICE 12.1
1. =40-32t.
EXERCISE 12.1 (page 564)
1. a.
b. We estimate that mtan=12.3. 1. 5. 4. 7. –4. 9. 0. 11. 2x+4.
13. 4q+5. 15. . 17. . 19. –4.
21. 0. 23. y=x+4. 25. y=–3x-7.
27. y= . 29. .
31. –3.000, 13.445. 33. –5.120, 0.038.35. For the x-values of the points where the tangent to thegraph of f is horizontal, the corresponding values of f¿(x)are 0. This is expected because the slope of a horizontal lineis zero and the derivative gives the slope of the tangent line.
When t=0.5 the object reaches its maximum height.3. 1.2 and 120%.
EXERCISE 12.3 (page 582)
1.
We estimate the velocity t=1 to be 5.0000 m/s.With differentiation the velocity is 5 m/s.3. a. 4 m; b. 5.5 m/s; c. 5 m/s.5. a. 8 m; b. 6.1208 m/s; c. 6 m/s.7. a. 2 m; b. 10.261 m/s; c. 9 m/s. 9. 0.65.
1. Figure 13.5 shows that the population reaches its finalsize in about 45 days.3. The tangent line will not coincide exactly with the curvein the first place. Smaller time steps could reduce the error.
PRINCIPLES IN PRACTICE 14.1
1. There is a relative maximum when x=1, and a relativeminimum when x=3.2. The drug is at its greatest concentration 2 hours after injection.
EXERCISE 14.1 (page 655)
1. Dec. on (–q, –1) and (3, q); inc. on (–1, 3); rel. min. (–1, –1); rel. max. (3, 4).3. Dec. on (–q, –2) and (0, 2); inc. on (–2, 0) and (2, q);rel. min. (–2, 1) and (2, 1); no rel. max.5. Inc. on (–q, –1) and (3, q); dec. on (–1, 3); rel max. when x=–1; rel. min. when x=3.7. Dec. on (–q, –1); inc. on (–1, 3) and (3, q); rel. min. when x=–1.9. Inc. on (–q, 0) and (0, q); no rel. min. or max.
11. Inc. on ; dec. on
rel. max. when x=
13. Dec. on (–q, –5) and (1, q); inc. on (–5, 1);rel. min. when x=–5; rel. max. when x=1.15. Dec. on (–q, –1) and (0, 1); inc. on (–1, 0) and (1, q);rel. max. when x=0; rel. min. when x=—1.
12
.
a 12
, q b ;a - q, 12b
dy
dx=
y + 1y
; d2y
dx2 = -y + 1
y3
49
xy2 - y
2x - x2y
-
y
x + y
= y c 3x
x2 + 2+
8x
9 1x2 + 9 2 -12 1x2 + 2 2
11 1x3 + 6x 2 d-
411a 1
x3 + 6xb 13x2 + 6 2 d
y c 32a 1
x2 + 2b 12x 2 +
49a 1
x2 + 9b 12x 2
2 a 1tb +
12a 1
2 - tb 1-1 2 =
5t - 82t 1 t - 2 2
1 + 2l + 3l2
1 + l + l2 + l3
1618x + 5 2 ln 2
4e2x + 1 12x - 1 2x2
2q + 1
+3
q + 2
1 - x ln xxex
ex a 1xb - 1 ln x 2 1ex 2
e2x
1 1x - 6 2 1x + 5 2 19 - x 22
c 1x - 6
+1
x + 5+
1x - 9
d
ex2 + 4x + 5ex2 + 4x + 5
1r2 + 5r
12r + 5 2 =2r + 5
r 1r + 5 2ex2
ex2
-
16125
y
11 - y 2 32 1y - 1 211 + x 2 2
18x3>2-
4y3-
1y3
- c 1x2 +
11x + 6 2 2 d
41x - 1 2 3
5015x - 6 2 3-
14 19 - r 2 3>2
-
10p6
d2h
dt2 = -32
13e13
2 13x + 1 2 2x c 3x
3x + 1+ ln 13x + 1 2 d
x1>x 11 - ln x 2x2x2x + 1 a 2x + 1
x+ 2 ln x b
12A 1x - 1 2 1x + 1 2
3x - 4c 1x - 1
+1
x + 1-
33x - 4
d
12x2 + 2 2 21x + 1 2 2 13x + 2 2 c
4x
x2 + 1-
2x + 1
-3
3x + 2d
21 - x2
1 - 2xc x
x2 - 1+
21 - 2x
dc 1x + 1
+2x
x2 - 2+
1x + 4
d
2x + 1 2x2 - 2 2x + 42
#
13x2 - 1 2 2 12x + 5 2 3 c 18x2
3x3 - 1+
62x + 5
dAN28 Answers to Odd-Numbered Problems �
17. Inc. on (–q, 1) and (3, q); dec. on (1, 3);rel. max. when x=1; rel. min. when x=3.
19. Inc. on and ; dec. on ;
rel. max. when x= ; rel. min. when x= .
21. Inc. on and ;
dec. on ; rel. max. when
x= ; rel. min. when x= .
23. Inc. on (–q, –1) and (1, q); dec. on (–1, 0) and (0, 1);rel. max. when x=–1; rel. min. when x=1.25. Dec. on (–q, –4) and (0, q); inc. on (–4, 0); rel. min. when x=–4; rel. max. when x=0.27. Inc. on (–q, ) and (0, ); dec. on ( , 0) and ( , q); rel. max. when x=— ; rel. min. when x=0.29. Inc. on (–q, –1), (–1, 0), and (0, q); never dec.;no rel. extremum.31. Dec. on (–q, 1) and (1, q); no rel. extremum.33. Dec. on (0, q); no rel. extremum.35. Dec. on (–q, 0) and (4, q); inc. on (0, 2) and (2, 4);rel. min. when x=0; rel. max. when x=4.37. Inc. on (–q, –3) and (–1, q); dec. on (–3, –2) and(–2, –1); rel. max. when x=–3; rel. min. when x=–1.
39. Dec. on and ;
inc. on ; rel. min. when
x= ; rel. max. when x=
41. Inc. on (–q, –2), , and (5, q); dec. on
; rel. max. when x= ; rel. min. when x=5.
43. Inc. on (–q, 0), , and (6, q); dec. on ;
rel. max. when x= ; rel. min. when x=6.
45. Dec. on (–q, q); no rel. extremum.
47. Dec. on ; inc. on ;
rel. min. when x= .
49. Dec. on (–q, 0); inc. on (0, q); rel. min. when x=0.51. Dec. on (0, 1); inc. on (1, q); rel. min. when x=1;no rel. max.
53. Dec. on (–q, 3); inc. on (3, q); rel. min. when x=3;intercepts: (7, 0), (–1, 0), (0, –7).
55. Dec. on (–q, –1) and (1, q); inc. on (–1, 1);rel. min. when x=–1; rel. max. when x=1;sym. about origin; intercepts: (— , 0), (0, 0).
57. Inc. on (–q, 1) and (2, q); dec. on (1, 2);rel. max. when x=1; rel. min. when x=2; intercept: (0, 0).
59. Inc. on (–2, –1) and (0, q); dec. on (–q, –2) and (–1, 0); rel. max. when x=–1; rel. min. when x=–2, 0;intercepts: (0, 0), (–2, 0).
13. Maximum: f(3)≠2.08; minimum: f(0)=0.15. a. –3.22, –0.78; b. 2.75; c. 9; d. 14,283.
EXERCISE 14.3 (page 666)
1. Conc. up (–q, 0), ; conc. down ;
inf. pt. when x= .
3. Conc. up (– ; conc down (7, q);inf. pt. when x=7.5. Conc. up (–q, – ), ( , q); conc down (– , );no inf. pt.7. Conc. down. (–q, q).9. Conc down. (–q, –1); conc. up (–1, q); inf. pt. when x=–1.
11. Conc. down. ; conc. up ;
inf. pt. when x= .
13. Conc. up (–q, –1), (1, q); conc. down (–1, 1); inf. pt. when x=—1.15. Conc. up (–q, 0); conc. down (0, q);inf. pt. when x=0.
17. Conc. up , ; conc. down ;
inf. pt. when x= .
19. Conc. down ;
conc. up ;
inf. pt. when x=0, .
21. Conc. up (–q, – ), ; conc. down (– , – ), ;inf. pt. when x=— , — .23. Conc. down (–q, 1); conc. up (1, q).25. Conc. down. (–q, – ), ( , q);conc. up (– , ); inf. pt. when x=— .
27. Conc. down. (–q, –3), ; conc. up ;
inf. pt. when x= .
29. Conc. up. (–q, q).31. Conc. down (–q, –2); conc. up (–2, q);inf. pt. when x=–2.33. Conc. down (0, e3/2); conc. up (e3/2, q); inf. pt. when x=e3/2.35. Int. (–3, 0), (–1, 0), (0, 3); dec. (–q, –2);inc. (–2, q); rel. min. when x=–2; conc. up (–q, q).
x
y
27
a 27
, q ba-3, 27b
1>131>131>131>131>13
1215112, 15 212151-12, 12 2 , 115, q 215
3 ; 152
a0, 3 - 15
2b , a 3 + 15
2, q b
1- q, 0 2 , a 3 - 152
, 3 + 15
2b
-72
, 13
a -72
, 13ba 1
3, q ba - q, -
72b
74
a 74
, q ba - q, 74b
12121212
q, 1 2 , 11, 7 20,
32
a0, 32ba 3
2, q b
f a 3122b = -
734
12
-193
x
y
1 3
2
1
x
y
1 4
1
x
y
1– 2
4
-12
a -2, -12ba -
12
, 1 bAN30 Answers to Odd-Numbered Problems �
37. Int. (0, 0), (4, 0); inc. (–q, 2); dec. (2, q); rel. max. when x=2; conc. down (–q, q).
39. Int. (0, –19); inc. (–q, 2), (4, q); dec. (2, 4);rel. max. when x=2; rel. min. when x=4;conc. down (–q, 3); conc. up (3, q); inf. pt. when x=3.
41. Int. (0, 0), (— , 0); inc. (–q, –2), (2, q); dec. (–2, 2); rel. max. when x=–2; rel. min. when x=2; conc. down (–q, 0); conc. up (0, q); inf. pt. when x=0;sym. about origin.
43. Int. (0, –3); inc. (–q, 1), (1, q); no rel. max. or min.;conc. down (–q, 1); conc. up (1, q); inf. pt. when x=1.
45. Int. (0, 0), ; inc. (–q, 0), (0, 1); dec. (1, q); rel. max. when x=1; conc. up ; conc. down (–q, 0),
; inf. pt. when x=0, x=2/3.
47. Int. (0, –2); dec. (–q, –2), (2, q); inc. (–2, 2);rel. min. when x=–2; rel. max. when x=2;conc. up (–q, 0); conc. down (0, q); inf. pt. when x=0.
49. Int. (0, –6); inc. (–q, 2), (2, q); conc. down (–q, 2);conc. up (2, q); inf. pt. when x=2.
51. Int. (0, 0), ; dec. (–q, –1), (1, q); inc. (–1, 1); rel. min. when x=–1; rel. max. when x=1;conc. up (–q, 0); conc. down (0, q); inf. pt. when x=0;sym. about origin.
55. Int. (0, 0), (—2, 0); inc. (–q, – ), (0, ); dec. (– , 0), ( , q); rel. max. when x=— ;rel. min. when x=0; conc. down (–q, – ), ( , q); conc. up (– , ); inf. pt. when x=— ; sym. about y-axis.//
57. Int. (0, 0), (8, 0); dec. (–q, 0), (0, 2); inc. (2, q);rel. min. when x=2; conc. up (–q, –4), (0, q); conc. down (–4, 0); inf. pt. when x=–4, x=0.
59. Int. (0, 0), (–4, 0); dec. (–q, –1); inc. (–1, 0), (0, q);rel. min. when x=–1; conc. up (–q, 0), (2, q); conc. down (0, 2); inf. pt. when x=0, x=2.
61. Int. (0, 0), ; inc. (–q, –1), (0, q);
dec. (–1, 0); rel. min. when x=0; rel. max. when x=–1;conc. down (–q, 0), (0, q).
5. Rel. max. when x=–3; rel. min. when x=3.7. Rel. min. when x=0; rel. max. when x=2.9. Test fails, when x=0 there is a rel. min. by first-deriv. test.
11. Rel. max. when x= ; rel. min. when x= .
13. Rel. min. when x=–5, –2; rel. max. when x= .-72
25. Dec. (–q, 0), (0, q); conc. down (–q, 0); conc. up (0, q); sym. about origin; asymptotes x=0, y=0.
27. Int. (0, 0); inc. (–q, –1), (–1, q); conc. up (–q, –1);conc. down (–1, q); asymptotes x=–1, y=1.
29. Dec. (–q, –1), (0, 1); inc. (–1, 0), (1, q); rel. min. when x=—1; conc. up (–q, 0), (0, q); sym. about y-axis; asymptote x=0.
31. Int. (0, –1); inc. (–q, –1), (–1, 0); dec. (0, 1), (1, q);rel. max. when x=0; conc. up (–q, –1), (1, q); conc. down (–1, 1); asymptotes x=1, x=–1, y=0; sym. about y-axis.
33. Int. (–1, 0), (0, 1); inc. (–q, 1), (1, q); conc. up (–q, 1); conc. down (1, q); asymptotes x=1, y=–1.
35. Int. (0, 0); inc. , (0, q); dec. ,
; rel. max. when x= ; rel. min. when x=0;
conc. down ; conc. up ;
asymptote x= .
37. Int. ; inc. dec.
; rel. max. when x= ; conc. up
; conc. down ;
asymptotes y=0, x= .
x
y
23
43–
, –113( )
-23
, x =43
a -23
, 43ba - q, -
23b , a 4
3, q b
13
a 13
, 43b , a 4
3, q b
a - q, -23b , a -
23
, 13b ; a0, -
98b
–16/49x
y
87
–
–x = 47
-47
a -47
, q ba - q, -47b
-87
a -47
, 0 ba -
87
, -47ba - q, -
87b
x
y
1
–1
x
y
1–1 –1
x
y
–1 1
2
x
y
1
–1
x
y
-43
12
-12
14
1212
-32
12
� Answers to Odd-Numbered Problems AN33
39. Int. ; dec.
inc. rel. min. when x= ;
conc. down ; conc. up ;
inf. pt. when x= ; asymptotes x= , y=0.
41. Int. (–1, 0), (1, 0); inc. (– , 0), (0, ); dec. (–q, – ), ( , q); rel. max. when x= ; rel. min. when x=– ; conc. down (–q, – ), (0, ); conc. up (– , 0), ( , q); inf. pt. when x=— ; asymptotes x=0, y=0; sym. about origin.
43. Int. (0, 1); inc. (–q, –2), (0, q); dec. (–2, –1), (–1, 0); rel. max. when x=–2; rel. min when x=0;conc. down (–q, –1); conc. up (–1, q); asymptote x=–1.
45. Int. (0, 5); dec. ; inc. ,
(1, q); rel. min. when x= ; conc. down ,
(1, q); conc. up ; asymptotes x= , x=1,
y=–1.
47.
49.
55. x≠—2.45, x≠0.67, y=2. 57. y≠0.48.
REVIEW PROBLEMS—CHAPTER 14 (page 681)
1. y=3, x=4, x=–4. 3. y= , x= .
5. x=0, 4. 7. x= , –1.
9. Inc. (1, 3); dec. on (–q, 1) and (3, q).11. Dec. on (–q, – ), (0, ), ( , );inc. on (– , – ), (– , 0), ( , q).
13. Conc. up on (–q, 0) and ;
conc. down on .a0, 12b
a 12
, q b16131316
16131316
-158
-23
59
x
y
–1 2
x
y
1
2
x
y
1
–1
13
–
, ( )13
72
-13
a -13
, 1 ba - q, -
13b1
3
a 13
, 1 ba - q, -13b , a -
13
, 13b
x
y
–1
–3
x
y
3
3–
161616161613
1313131313
x
y
, ( )92
127
92
, (— )32
124—
——
92
-92
a -92
, 92b , a 9
2, q ba - q, -
92b
-32
a -32
, 92b ;
a - q, -32b , a 9
2, q b ;a 3
2, 0 b , a0,-
127b
AN34 Answers to Odd-Numbered Problems �
15. Conc. down on ; conc. up on .
17. Conc. up on ;
conc. down on .
19. Rel. max. at x=1; rel. min. at x=2.21. Rel. min. at x=–1.
23. Rel. max. at x= ; rel. min. at x=0.
25. At x=3. 27. At x=1. 29. At x=2_ .31. Maximum: f(2)=16; minimum: f(1)=–1.
33. Maximum: f(0)=0; minimum: .
35. a. f has no relative extrema;b. f is conc. down on (1, 3); inf. pts.: (1, 2e–1), (3, 10e–3).37. Int. (–4, 0), (6, 0), (0, –24); inc. (1, q); dec. (–q, 1);rel. min. when x=1; conc. up (–q, q).
39. Int. (0, 20); inc. (–q, –2), (2, q); dec. (–2, 2);rel. max. when x=–2; rel. min. when x=2;conc. up (0, q); conc. down (–q, 0); inf. pt. when x=0.
41. Int. (0, 0); inc. (–q, q); conc. down (–q, 0); conc. up (0, q); inf. pt. when x=0; sym. about origin.
43. Int. (–5, 0); inc. (–10, 0); dec. (–q, –10), (0, q); rel. min. when x=–10; conc. up (–15, 0), (0, q);conc. down (–q, –15); inf. pt. when x=–15;horiz. asym. y=0; vert. asym. x=0.
45. Int. (0, 0); inc. ; dec. , ;
rel. max. when x= ; conc. up ;
conc. down ; inf. pt. when x= ;
horiz. asym. y=0; vert. asym. x= .
47. Int. (0, 1); inc. (0, q); dec. (–q, 0); rel. min. when x=0; conc. up (–q, q); sym. about y-axis.
49. a. False; b. false; c. true; d. false; e. false.51. q>2.57. Rel. max. (–1.32, 12.28); rel. min. (0.44, 1.29).59. x=–0.60.
MATHEMATICAL SNAPSHOT—CHAPTER 14 (page 685)
1. The data for 1998–2000 fall into the same pattern as the1959–1969 data.
7. a. e–2-e–6≠0.133; b. 1-e–4≠0.982;c. e–9≠0.0001; d. 1-e–2≠0.865.
9. a. b. c. d. 1; e. f.
g. ; h. . 11. 5 min. 13. e–3≠0.050.
EXERCISE 18.2 (page 865)
1. a. 0.4641; b. 0.3239; c. 0.8980; d. 0.9983; e. 0.9147;f. 0.4721. 3. 0.13. 5. –1.08. 7. 0.34.9. a. 0.9970; b. 0.0668; c. 0.0873. 11. 0.3085.13. 0.8185. 15. 8. 17. 9.68%. 19. 90.82%.21. a. 1.7%; b. 85.6.
13. 4480; if a staff manager with an M.B.A. degree had anextra year of work experience before the degree, the manager would receive $4480 per year in extra compensation.15. a. –1.015; –0.846;b. One for which w=w0 and s=s0.
17. for VF>0. Thus if x increases and VF
and Vs are fixed, then g increases.
19. a. When pA=8 and pB=64, and
b. Demand for A decreases by approximately
units.
21. a. No; b. 70%. 23. .
25. .
EXERCISE 19.4 (page 898)
1. . 3. . 5. . 7. .
9. . 11. . 13. . 15. .
17. 4. 19. .
21. a. 36; b. With respect to qA, ; with respect to qB, .
15. (122, 127), rel. max. 17. (–1, –1), rel. min.19. (0, –2), (0, 2), neither. 21. l=24, k=14.23. pA=80, pB=85.25. qA=48, qB=40, pA=52, pB=44, profit=3304.27. qA=3, qB=2. 29. 1 ft by 2 ft by 3 ft.
31. , rel. min. 33. a=–8, b=–12, d=33.
35. a. 2 units of A and 3 units B;b. Selling price for A is 30 and selling price for B is 19.Relative maximum profit is 25.37. a. P=5T(1-e–x)-20x-0.1T2;c. Relative maximum at (20, ln 5); no relative extremum at
.
EXERCISE 19.8 (page 922)
1. (2, –2). 3. . 5. .
7. . 9. . 11. (3, 3, 6).
13. Plant 1, 40 units; plant 2, 60 units.15. 74 units (when l=8, k=7).17. $15,000 on newspaper advertising and $45,000 on TV advertising.19. x=5, y=15, z=5.21. x=12, y=8. 23. x=10, y=20, z=5.
EXERCISE 19.9 (page 929)
1. =0.98+0.61x; 3.12. 3. =0.057+1.67x; 5.90.5. =82.6-0.641p. 7. =100+0.13x; 105.2.9. =8.5+2.5x.11. a. =35.9-2.5x; b. =28.4-2.5x.
EXERCISE 19.11 (page 936)
1. 18. 3. . 5. . 7. 3. 9. 324. 11. .
13. . 15. –1. 17. . 19. .
21. . 23. e–4-e–2-e–3+e–1. 25. .
REVIEW PROBLEMS—CHAPTER 19 (page 939)
1.
3.
5. 8x+6y; 6x+2y. 7. .
9. . 11. . 13. 2(x+y).
15. xzeyz ln z; +yeyz ln z=eyz .
17. . 19. 2(x+y)er+2 .
21. . 23. .
25. Competitive. 27. (2, 2), rel. min.29. 4 ft by 4 ft by 2 ft.31. A, 89 cents per pound; B, 94 cents per pound.33. (3, 2, 1). 35. =12.67+3.29x
37. 8. 39. .
MATHEMATICAL SNAPSHOT—CHAPTER 19 (page 942)
1. y=9.50e–0.22399x+5. 3. T=79e–0.01113t+45.
EXERCISE A.1 (page 948)
1.
x
y
105
(0, 0)
(3, 5)
(4, 7)
(8, 10)
(10, 10)10
5
130
y
∂P
∂l= 14l-0.3k0.3;
∂P
∂k= 6l0.7k-0.72x + 2y + z
4z - x
a x + 3y
r + sb ; 2 a x + 3y
r + sb1
64
a 1z
+ y ln z beyz
z
2xzex2yz 11 + x2yz 2y
x2 + y2
y
1x + y 2 2; -x
1x + y 2 2
y
x
z
y
x
z
3
9
92
38
124
-274
e2
2- e +
12
83
-585
23
14
yyy
yqyy
a 23
, 43
, -43b16, 3, 2 2
a 43
, -43
, -83ba3,
32
, -32b
a5, ln 54b
a 10537
, 2837b
a0, 12ba4,
12b ,
a 12
, 14b
a -14
, 12b ,
a -2, 32b
a 143
, -133b
∂w
∂s=
∂w
∂x ∂x
∂s+
∂w
∂y ∂y
∂s;
∂c
∂pA= -
14
and ∂c
∂pB=
54
� Answers to Odd-Numbered Problems AN43
3.
5.
7. 75. 9. Between 1990 and 1993, 1995 and 1998, 1999 and 2000; positive. 11. Between 1994 and 1995; zero.13. Between 1993 and 1994. 15. 75 students; 1990.17. a. Possible graph:
; b. Wednesday.
19. a. ;
b. approximately 85 mi; c. between 5 and 6 h; 0;d. between 3 and 5 h; The slope of the line graph duringthis time interval is greater than the slope of the line graphduring the remaining intervals.
21. a. ;
b. between 6:00 A.M. and 8:00 A.M.;c. between 12:00 P.M. and 2:00 P.M.; 0;d. the number of fish caught per hour remained constant.
23. a. C=100+40r; b. $500; c. 22 reels.25. a. h=–16t¤+80t; b. 2.5 sec, 100 ft.27. a.
;
b. N=2000(3) ; c. 118,098,000 bacteria.29. a. (2, 1.3) and (6.5, 34.1); b. Answers may vary,but should be close to y=3.1x+1.5;c. Answers may vary, but should be close to y=44.9.
9. 4.5 in. per yr. 11. $42 per h.13. a. 3.5 degrees per day; b. –1.25 degrees per day;c. 1 degree per day; d. ≠0.59 degree per day.15. a. 0; b. 0; c. 0; d. 0. 17. a. 7; b. 13; c. h+8;d. 2xº+h+2. 19. a. –2; b. –2; c. –2; d. –2;e. Since g(x) is linear, the average rate of change between any two points is constant. 21. x(t)=2t+3.23. Possible graph:
25. Average cost per unit over the interval.
EXERCISE A.4 (page 967)
1. Average. 3. Instantaneous. 5. –8. 7. .
9. 1. 11. y=x-1. 13. y= .
15. 0. 17. 5. 19. 20x. 21. .
23. . 25. .
27. . 29. =0.1q+28;
$35.50 per rug. 31. =–32t+32; a. 32 ft/sec;
b. –32 ft/sec; c. –64 ft/sec.
dh
dt
dc
dq-
52112 - 5x
+ 20x
5215x - 11
15112 - 5x 2 2
-5
15x + 11 2 2
12
x +12
-19
x
y
y
40
x5–5
y
10
x5–5
t
t
A
105
10,000
5000
Number of daysof decay
Am
ount
of s
ubst
ance
(mill
igra
ms)
x
y
–10 10–5
70
x
y
10
35
x
y
–4 32–1
5 (32, 5)
(8, 3)
(2, 1)
(1, 0)
( , –1)12
� Answers to Odd-Numbered Problems AN45
t 0 1 2 3 4 5
N 2000 6000 18,000 54,000 162,000 486,000
EXERCISE A.5 (page 972)
In Problems 1–13, answers are assumed to be expressed insquare units.
1. . 3. 34. 5. 28. 7. a. 41; b. 44;
c. 42; d. 42; e. parts (c) and (d).9. a. �12.57; b. �9.98; c. �11.36; d. �11.98; e. part (d).11. a. 54; b. 42; c. trapezoid.13. a. 104; b. 86; c. trapezoid.15. ; The area under f(x) can be
divided into 2 sections (seegraph). The top section isequivalent to the areaunder g(x), so they havethat area in common. Thebottom section is a rectangle that the areaunder g(x) does not include.
EXERCISE A.6 (page 977)
1. 12, 17, t. 3. 168. 5. 532. 7. . 9. .
11. . 13. 520. 15. 5. 17. 37,750.
19. 14,980. 21. 295,425. 23. .
25. 8- . 27. 4.500625 square units.
EXERCISE A.7 (page 985)
1. ; 20. 3. .
5. . 7. .
9. ; positive.
11. ; positive.
13. ; positive.
15. a. 7b; b. 70. 17. a. ; b. 170.
19. a. 14; b. G(x)=2x+b, where b can be any real number; c. 14.
21. 30. 23. –14. 25. 25 . 27. e‹-1≠19.09.
EXERCISE A.8 (page 993)
1. Integral. 3. Function itself. 5. Derivative.7. Function itself. 9. a. 50; The cost of the rental is $50.00 when you drive the truck 50 miles; b. 0.60; When you have driven the truck 50 miles, the cost is increasing at the rate of $0.60 per mile. 11. a. b(t)=300t;b. b�(t)=300; The employee’s bonus increases at the rate of $300 per year; c. The integral dt approximates the sum of an employee’s annual bonuses during the first ten years with the company. 13. a. 23; b. 2; In 1995,the number of books that Xul reads annually was increasing at the rate of about 2 books per year; c. 140.26;Between 1991 and 2000, Xul read about 140 books.15. a. 8; 11.95; In 2006, the program’s budget would be $8 billion with model bl and $11.95 billion with be; b. 1.6;1.11; In 2006, the program’s budget is increasing at the rate of $1.6 billion per year with model bl and about $1.11 billion per year with be; c. 20; 38.36; In the first five years of the program, the cumulative budget would be about $20 billion with model bl and about $38.36 billion with be; d. be.; e. bl;f. be. 17. a. 0.012 mi/sec; b. 0.002 mi/sec2;c. 0.035 mile.
REVIEW PROBLEMS (page 995)
1.
3. between October and November.5. C=550+22.50x.
t
A
4321
180
140
90
(0, 125)
(1, 98)
(3, 150)
(2, 175)
(4, 150)
Am
ount
(do
llars
)
Number of monthsafter October
110
0 b1t2
12
32
b2 + 2b
x
y
3
x
y
4–2
x
y
6
35
-513x + 5 2 dx3
5
-21x2 + x + 2 2 dx
39
48 dx8 a n + 1
nb + 12
41n+1212n+123n2
4 2325
a8
i = 12i
a8
j = 35ja
60
i = 36i
x
y
f(x)
g(x)
5
8
412
+p
4
AN46 Answers to Odd-Numbered Problems �
7. a. , quadratic;
b. h=–16t¤+100t; c. 24 ft; d. 6.25 s.9. a. –3, –3, –3, –3, linear; b. 1, 3, 5, 7, nonlinear.11. a. 300 kilobytes;b. ;
c. ≠–1.26 kilobytes per second,≠–1.18 kilobytes persecond,≠–0.76 kilobytes per second;d. The negative sign indicates that as the amount of time left decreases, the amount of the document which has been downloaded increases; e. 302 seconds to 204 seconds.
13. x(t)=4t-1. 15. y= .
17. . 19. 29 square units.
21. a. �7.07 square units; b. �5.07 square units;c. �6.145 square units; d. �6.57 square units; e. part (d).23. a. 45 square units; b. 42.5 square units;
c. neither is better. 25. 513. 27. .
29. 2.999975 square units.
31. 33. log x dx.
35.
37.
39. a. ; b. 80. 41. 100,000. 43. 36.
45. a. 2103.64; The energy costs for a 1900 square-foot home were about $2103.64 in 2001; b. 63.11; In 2001, the energy costs for a 1900 square-foot home were increasing at a rate of about $63.11 per year; c. 42,455.27;The cumulative energy costs for a 1900 square-foot home between 1970 and 2001 were about $42,455.27.47. a. 0.015 mi/sec; b. 0.005 mi/sec¤; c. 0.03 mi.