Chapter 14

Section 14.1

1. True

2. False

3. (d)

4. True

5. (a) 36

(b) 9

7. (a) 60

(b) 164

9. 320

11. x

13.

15. e − 1

17.

19. 27

21.

23. 0

25.

27.

29. e − 1

31. 0

33. 1 + e2

35.

37. 30

39. 28

41. 5(1 − e)

43.

45.

47.

49.

51.

53.

55. 5 cubic units

57. cubic units

59. 1 cubic unit

61. 3 ln 2 cubic units

63. (e − 1)2(e + 1) cubic units

65. cubic units

67. See the Student Solutions Manual.

69.

Section 14.2

1. x-simple region

2. True

3. True

4. Answers will vary.

5. (a)

(b)

(c)

7. (a)

(b)

(c)

9.

11.

13. 1

15.

17. 6

19.

21.

23.

25.

27.

29. square units

31. A = 72 square units

33. A = 2 square units

35. square units

37.

39.

41.

43.

45. 14

47. 0

49. square units

51. cubic units

53. cubic units

55. V = 8π cubic units

57. cubic units

59. cubic units

61. (a)

(b)

(c)

63. (a)

(b)

(c) 1

65. (a)

(b)

(c)

67. (a)

(b)

(c)

69.

71.

73. The solid is the volume under the hemisphere in the first octant.

75. The solid is a rectangular box with height z = 3 units, with a rectangular base of dimensions x = 4 units and y = 1 unit.

77. (a) 0

(b)

79. (a)

(b)

81.

83. Answers will vary.

85. 4

87. 12 − 4e

89. See the Student Solutions Manual.

Section 14.3

1. f (r, θ) = 2r

2. r dr dθ

3. False

4. True

5.

7.

9.

11.

13.

15.

17.

19.

21. 0

23. 6

25.

27. 0

29.

31. 4π

33.

35.

37.

39. 21π

41.

43. cubic units

45. cubic units

47. square units

49. square units

51. square units

53.

55. cubic meters

57. (a)

(b) square units

59. square units.

61. (a) See the Student Solutions Manual.

(b) See the Student Solutions Manual.

(c)

(d) See the Student Solutions Manual.

(e) See the Student Solutions Manual.

Section 14.4

1. Mass

2. False

3.

4. False

5. True

6. False

7. and

9. M = 64 and

11. and

13. , where k is the constant of proportionality, and

15. M = 5k, where k is the constant of proportionality, and

17. , where k is the constant of proportionality, and

19. , where k is the constant of proportionality, and

21. Ix = 2ρ

23.

25.

27. M = 2πk ln 2, where k is the constant of proportionality

29. M = ka(π − 2) ≈ 1.142ka, where k is the constant of proportionality, and

31.

33. and

35.

37. (a) , where k is the constant of proportionality. As a → 0+, M.

(b) I = (b2a2), where k is the constant of proportionality. As a → 0+, Ikπb2.

39. See the Student Solutions Manual.

41. See the Student Solutions Manual.

43. (a) See the Student Solutions Manual.

(b)

(c)

Section 14.5

1. True

2. False

3. S = 3π

5.

7.

9.

11.

13.

15. S = 8π

17.

19.

21.

23. (a)

(b) S ≈ 55.436

25. See the Student Solutions Manual.

27. See the Student Solutions Manual.

29. \(S = 2 R^2 (\pi - 2)\) square units

Section 14.6

1. True

2. False

3. True

4. False

5.

7. 1

9. e − 1

11.

13. 81

15. 2(e − 2)

17.

19.

21.

23.

25. −0.4142

27.

29.

31. (a) The semi-cylinder is given by x2 + y2 = 4 and the planes x = 0, z = 0, and z = 1.

(b)

33. (a) The solid is bounded by y = x2 and the planes z = 0, x = 1, and z = y.

(b)

35. cubic units

37. cubic units

39. cubic units

41. cubic units

43. M = ka5, where k is the constant of proportionality

45. , where k is the constant of proportionality

47. , where k is the constant of proportionality

49.

51. See the Student Solutions Manual. When a = b = c, the formula for the volume of an ellipsoid reduces to the formula for the volume of a sphere.

53. V = 2 cubic units

55. See the Student Solutions Manual.

Section 14.7

1. x = r cos θ, y = r sin θ, and z = z

2. r = 2z

3. dV = r dr dθ dz

4. True

5.

7.

9. (2, 0, 4)

11.

13.

15. (1, 0, 8)

17. (0, 2, 0)

19. The triple integral represents the volume of a hemisphere of radius 1 to the right of the xz-plane, that is y ≥ 0.

21. The triple integral represents the volume inside the vertical cylinder x2 + y2 = 4, bounded below by the xy-plane and bounded above by the surface of the cone .

23.

25.

27. 24π

29. 0

31. 0

33. cubic units

35. V = 64π cubic units

37. cubic units

39. , where k is the constant of proportionality

41. , where k is the constant of proportionality

43.

45.

47.

49.

51. (a)

(b) r ≈ 6.083 cm

53.

Section 14.8

1. Origin

2. z-axis

3. False

4. True

5. dV = ρ2 sin ϕ dρ dθ dϕ

6. Sphere

7.

9.

11.

13.

15.

17.

19.

21. 0

23.

25.

27.

29.

31.

33. 18π and

35.

37. , where k is the constant of proportionality

39.

41.

43. , where δ is the mass density

45.

47. (a) k = 1.238 × 10−6 m−1 and D0 = 2500 kg/m3

(b) The calculated mass of Dione is 1.10 × 1021 kg, which differs from the measured mass by only 4.76%. The density model for the asteroid is reasonable.

49. See the Student Solutions Manual.

Section 14.9

1.

2. True

3.

5.

7.

9.

11.

13.

15.

17. A = 6π square units

19. (a)

(b)

(c)

(d)

21. (a)

(b)

(c)

(d) 0

23. 0

25. 16π

27. (a)

(b)

(c)

(d)

29. (a)

(b)

(c)

(d) 2(sin 3 − sin 1)

31. square units

33. V = 36 cubic units

35. cubic units

37. See the Student Solutions Manual.

Review Exercises

1.

3.

5.

7. (a) The midpoint Riemann sum is 32.

(b) The largest Riemann sum is 80, the lowest Riemann sum is −16, and their average is 32.

(c) 32

9.

11. V = 6 cubic units

13.

15. V = 6 cubic units

17. cubic units

19.

21. A = π square units

23. M = 104k, where k is the constant of proportionality

25.

27.

29.

31.

33.

35. cubic units

37. (a) (r, θ, z) = (3, 0, 4)

(b)

39. (a)

(b)

41. cubic units

43.

45.

47.

49. 16π

51.

53.

55.

57.

59. 203

61. 0