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1068 CAPÍTULO 15 Análisis vectorial

En los ejercicios 53 a 56, usar un sistema algebraico por computadora

y representar el rotacional del campo vectorial.

En los ejercicios 57 a 62, determinar si el campo vectorial F es

conservativo. Si lo es, calcular una función potencial para él.

En los ejercicios 63 a 66, calcular la divergencia del campo vectorial

F.

En los ejercicios 67 a 70, calcular la divergencia del campo vectorial

F en el punto dado.

En los ejercicios 75 y 76, calcular

En los ejercicios 77 y 78, hallar

77.

78.

En los ejercicios 79 y 80, hallar

En los ejercicios 81 y 82, hallar div (rot F) · ( F).

81.

82.

En los ejercicios 83 a 90, demostrar la propiedad para los campos

vectoriales F y G y la función escalar ƒ. (Suponer que las

derivadas parciales requeridas son continuas.)

90. div(rot F) 0 (Teorema 15.3)

En los ejercicios 91 a 93, sea

y

91. Probar que 92. Probar que

93. Probar que

¿Verdadero o falso?

En los ejercicios 95 a 98, determinar si la

declaración es verdadera o falsa. Si es falsa, explicar por qué o

dar un ejemplo que demuestre su falsedad.

95. Si F(x, y) 4xi y 2 j, entonces cuando (x, y) Æ

(0, 0).

96. Si y está en el eje y positivo, entonces

el vector apunta en la dirección y negativa.

97. Si es un campo escalar, entonces el rotacional tiene sentido.

98. Si es un campo vectorial y rot F = 0, entonces F es irrotacional

pero no conservativo.

F

f

f

x, y

Fx, y 4xi y 2 j

Fx, y → 0

f n nf n2 F.

1

f F f 3.

ln f F f 2.

Fx, y, z .

fx, y, z

Fx, y, z xi yj zk,

Fx, y, z x 2 zi 2xzj yzk

Fx, y, z xyzi yj zk

Fx, y, z x 2 zi 2xzj yzk

Fx, y, z xyzi yj zk

Desarrollo de conceptos

71. Definir un campo vectorial en el plano y en el espacio. Dar

algunos ejemplos físicos de campos vectoriales.

72. ¿Qué es un campo vectorial conservativo y cuál es su criterio

en el plano y en el espacio?

73. Definir el rotacional de un campo vectorial.

74. Definir la divergencia de un campo vectorial en el plano y en

el espacio.

9. 10.

11. 12.

13. 14.

15. 16.

In Exercises 17–20, use a computer algebra system to graph

several representative vectors in the vector field.

17.

18.

19.

20.

47.

48.

In Exercises 49–52, find curl F for the vector field at the given

point.

49.

50.

51.

52. 3, 2, 0

F x, y, z e xyz i j k

0, 0, 1

F x, y, z e x sen yi e x cos yj

2, 1, 3

F x, y, z x 2 zi 2xzj yzk

2, 1, 3

F x, y, z xyzi xyzj xyzk

Punto

Campo vectorial

F x, y

2xi

2yj

x 2 y 2 2

F x, y e x cos yi sen yj

F x, y, z xi yj zk

F x, y, z

xi yj zk

x 2 y 2 z 2

F x, y 2y 3x i 2y 3x j

F x, y

1

8 2xyi y 2 j

F x, y, z xi yj zk

F x, y, z i j k

F x, y x 2 y 2 i j

F x, y 4xi yj

F x, y

xi

F x, y, z

3yj

F x, y yi 2xj

F x, y yi xj

CAS

In Exercises 53–56, use a computer algebra system to find the

rot F for the vector field.

53.

54.

55.

56.

In Exercises 57–62, determine whether the vector field F is

conservative. If it is, find a potential function for the vector field.

57.

58.

59.

60.

61.

62.

In Exercises 63–66, find the divergence of the vector field F.

63.

64.

65.

66.

In Exercises 67–70, find the divergence of the vector field F at

the given point.

67.

68.

69.

70.

In Exercises 75 and 76, find rot

75. 76.

In Exercises 77 and 78, find rot

77.

78.

In Exercises 79 and 80, find

79. 80.

In Exercises 81 and 82, find

81.

82.

In Exercises 83–90, prove the property for vector fields F and G

and scalar function

(Assume that the required partial

derivatives are continuous.)

83.

84.

85.

86.

87.

88.

89.

90. (Theorem 15.3)

In Exercises 91–93, let

and let

91. Show that 92. Show that

93. Show that

True or False?

In Exercises 95–98, determine whether the

statement is true or false. If it is false, explain why or give an

example that shows it is false.

95. If then as

96. If and is on the positive -axis, then

the vector points in the negative -direction.

97. If is a scalar field, then rot is a meaningful expression.

98. If is a vector field and then is irrotational but

not conservative.

F

rot F 0,

F

f

f

y

y

x, y

F x, y 4xi y 2 j

x, y → 0, 0 .

F x, y → 0

F x, y 4xi y 2 j,

f n nf n 2 F.

1

f

F

f 3.

ln f

F

f 2.

fx, y, z F x, y, z .

F x, y, z

xi yj zk,

div rot F 0

div f F f div F f F

f F f F f F

f F F

div F G rot F G F rot G

div F G div F div G

rot f f 0

rot F G rot F rot G

f.

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

div rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

div F G F G .

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

F G F G .

3, 2, 1

F x, y, z ln xyz i j k

3, 0, 0

F x, y, z e x sen yi e x cos yj z 2 k

2, 1, 3

F x, y, z x 2 zi 2xzj yzk

2, 1, 1

F x, y, z xyzi xyj zk

Punto

Campo vectorial

F x, y, z ln x 2 y 2 i xyj ln y 2 z 2 k

F x, y, z senxi cos yj z 2 k

F x, y xe x i ye y j

F x, y x 2 i 2y 2 j

F x, y, z

x

x 2 y 2 i y

x 2 y 2 j k

F x, y, z

z

y i

xz

y 2 j

x

y k

F x, y, z ye z i ze x j xe y k

F x, y, z sen zi sen xj sen yk

F x, y, z y 2 z 3 i 2xyz 3 j 3xy 2 z 2 k

F x, y, z xy 2 z 2 i x 2 yz 2 j x 2 y 2 zk

F x, y, z x 2 y 2 z 2 i j k

F x, y, z sen x y i sen y z j sen z x k

F x, y, z

yz

y z i xz

x z j xy

x

y k

F x, y, z arctan x y i ln x2 y 2 j k

1068 Chapter 15 Vector Analysis

CAS

71. Define a vector field in the plane and in space. Give some

physical examples of vector fields.

72. What is a conservative vector field, and how do you test for

it in the plane and in space?

73. Define the rot of a vector field.

74. Define the divergence of a vector field in the plane and in

space.

WRITING ABOUT CONCEPTS

94. (a) Sketch several representative vectors in the vector field

given by

(b) Sketch several representative vectors in the vector field

given by

(c) Explain any similarities or differences in the vector

fields y G x, y .

F x, y

G x, y

xi

yj

x 2 y 2.

F x, y

xi

yj

x 2 y 2.

CAPSTONE

In Exercises 53–56, use a computer algebra system to find the

rot F for the vector field.

53.

54.

55.

56.

In Exercises 57–62, determine whether the vector field F is

conservative. If it is, find a potential function for the vector field.

57.

58.

59.

60.

61.

62.

In Exercises 63–66, find the divergence of the vector field F.

63.

64.

65.

66.

In Exercises 67–70, find the divergence of the vector field F at

the given point.

67.

68.

69.

70.

In Exercises 75 and 76, find rot

75. 76.

In Exercises 77 and 78, find rot

77.

78.

In Exercises 79 and 80, find

79. 80.

In Exercises 81 and 82, find

81.

82.

In Exercises 83–90, prove the property for vector fields F and G

and scalar function

(Assume that the required partial

derivatives are continuous.)

83.

84.

85.

86.

87.

88.

89.

90. (Theorem 15.3)

In Exercises 91–93, let

and let

91. Show that 92. Show that

93. Show that

True or False?

In Exercises 95–98, determine whether the

statement is true or false. If it is false, explain why or give an

example that shows it is false.

95. If then as

96. If and is on the positive -axis, then

the vector points in the negative -direction.

97. If is a scalar field, then rot is a meaningful expression.

98. If is a vector field and then is irrotational but

not conservative.

F

rot F 0,

F

f

f

y

y

x, y

F x, y 4xi y 2 j

x, y → 0, 0 .

F x, y → 0

F x, y 4xi y 2 j,

f n nf n 2 F.

1

f

F

f 3.

ln f

F

f 2.

fx, y, z F x, y, z .

F x, y, z

xi yj zk,

div rot F 0

div f F f div F f F

f F f F f F

f F F

div F G rot F G F rot G

div F G div F div G

rot f f 0

rot F G rot F rot G

f.

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

div rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

div F G F G .

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

F G F G .

3, 2, 1

F x, y, z ln xyz i j k

3, 0, 0

F x, y, z e x sen yi e x cos yj z 2 k

2, 1, 3

F x, y, z x 2 zi 2xzj yzk

2, 1, 1

F x, y, z xyzi xyj zk

Punto

Campo vectorial

F x, y, z ln x 2 y 2 i xyj ln y 2 z 2 k

F x, y, z senxi cos yj z 2 k

F x, y xe x i ye y j

F x, y x 2 i 2y 2 j

F x, y, z

x

x 2 y 2 i y

x 2 y 2 j k

F x, y, z

z

y i

xz

y 2 j

x

y k

F x, y, z ye z i ze x j xe y k

F x, y, z sen zi sen xj sen yk

F x, y, z y 2 z 3 i 2xyz 3 j 3xy 2 z 2 k

F x, y, z xy 2 z 2 i x 2 yz 2 j x 2 y 2 zk

F x, y, z x 2 y 2 z 2 i j k

F x, y, z sen x y i sen y z j sen z x k

F x, y, z

yz

y z i xz

x z j xy

x

y k

F x, y, z arctan x y i ln x2 y 2 j k

1068 Chapter 15 Vector Analysis

CAS

71. Define a vector field in the plane and in space. Give some

physical examples of vector fields.

72. What is a conservative vector field, and how do you test for

it in the plane and in space?

73. Define the rot of a vector field.

74. Define the divergence of a vector field in the plane and in

space.

WRITING ABOUT CONCEPTS

94. (a) Sketch several representative vectors in the vector field

given by

(b) Sketch several representative vectors in the vector field

given by

(c) Explain any similarities or differences in the vector

fields y G x, y .

F x, y

G x, y

xi

yj

x 2 y 2.

F x, y

xi

yj

x 2 y 2.

CAPSTONE

In Exercises 53–56, use a computer algebra system to find the

rot F for the vector field.

53.

54.

55.

56.

In Exercises 57–62, determine whether the vector field F is

conservative. If it is, find a potential function for the vector field.

57.

58.

59.

60.

61.

62.

In Exercises 63–66, find the divergence of the vector field F.

63.

64.

65.

66.

In Exercises 67–70, find the divergence of the vector field F at

the given point.

67.

68.

69.

70.

In Exercises 75 and 76, find rot

75. 76.

In Exercises 77 and 78, find rot

77.

78.

In Exercises 79 and 80, find

79. 80.

In Exercises 81 and 82, find

81.

82.

In Exercises 83–90, prove the property for vector fields F and G

and scalar function

(Assume that the required partial

derivatives are continuous.)

83.

84.

85.

86.

87.

88.

89.

90. (Theorem 15.3)

In Exercises 91–93, let

and let

91. Show that 92. Show that

93. Show that

True or False?

In Exercises 95–98, determine whether the

statement is true or false. If it is false, explain why or give an

example that shows it is false.

95. If then as

96. If and is on the positive -axis, then

the vector points in the negative -direction.

97. If is a scalar field, then rot is a meaningful expression.

98. If is a vector field and then is irrotational but

not conservative.

F

rot F 0,

F

f

f

y

y

x, y

F x, y 4xi y 2 j

x, y → 0, 0 .

F x, y → 0

F x, y 4xi y 2 j,

f n nf n 2 F.

1

f

F

f 3.

ln f

F

f 2.

fx, y, z F x, y, z .

F x, y, z

xi yj zk,

div rot F 0

div f F f div F f F

f F f F f F

f F F

div F G rot F G F rot G

div F G div F div G

rot f f 0

rot F G rot F rot G

f.

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

div rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

div F G F G .

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

F G F G .

3, 2, 1

F x, y, z ln xyz i j k

3, 0, 0

F x, y, z e x sen yi e x cos yj z 2 k

2, 1, 3

F x, y, z x 2 zi 2xzj yzk

2, 1, 1

F x, y, z xyzi xyj zk

Punto

Campo vectorial

F x, y, z ln x 2 y 2 i xyj ln y 2 z 2 k

F x, y, z senxi cos yj z 2 k

F x, y xe x i ye y j

F x, y x 2 i 2y 2 j

F x, y, z

x

x 2 y 2 i y

x 2 y 2 j k

F x, y, z

z

y i

xz

y 2 j

x

y k

F x, y, z ye z i ze x j xe y k

F x, y, z sen zi sen xj sen yk

F x, y, z y 2 z 3 i 2xyz 3 j 3xy 2 z 2 k

F x, y, z xy 2 z 2 i x 2 yz 2 j x 2 y 2 zk

F x, y, z x 2 y 2 z 2 i j k

F x, y, z sen x y i sen y z j sen z x k

F x, y, z

yz

y z i xz

x z j xy

x

y k

F x, y, z arctan x y i ln x2 y 2 j k

1068 Chapter 15 Vector Analysis

CAS

71. Define a vector field in the plane and in space. Give some

physical examples of vector fields.

72. What is a conservative vector field, and how do you test for

it in the plane and in space?

73. Define the rot of a vector field.

74. Define the divergence of a vector field in the plane and in

space.

WRITING ABOUT CONCEPTS

94. (a) Sketch several representative vectors in the vector field

given by

(b) Sketch several representative vectors in the vector field

given by

(c) Explain any similarities or differences in the vector

fields y G x, y .

F x, y

G x, y

xi

yj

x 2 y 2.

F x, y

xi

yj

x 2 y 2.

CAPSTONE

In Exercises 53–56, use a computer algebra system to find the

rot F for the vector field.

53.

54.

55.

56.

In Exercises 57–62, determine whether the vector field F is

conservative. If it is, find a potential function for the vector field.

57.

58.

59.

60.

61.

62.

In Exercises 63–66, find the divergence of the vector field F.

63.

64.

65.

66.

In Exercises 67–70, find the divergence of the vector field F at

the given point.

67.

68.

69.

70.

In Exercises 75 and 76, find rot

75. 76.

In Exercises 77 and 78, find rot

77.

78.

In Exercises 79 and 80, find

79. 80.

In Exercises 81 and 82, find

81.

82.

In Exercises 83–90, prove the property for vector fields F and G

and scalar function

(Assume that the required partial

derivatives are continuous.)

83.

84.

85.

86.

87.

88.

89.

90. (Theorem 15.3)

In Exercises 91–93, let

and let

91. Show that 92. Show that

93. Show that

True or False?

In Exercises 95–98, determine whether the

statement is true or false. If it is false, explain why or give an

example that shows it is false.

95. If then as

96. If and is on the positive -axis, then

the vector points in the negative -direction.

97. If is a scalar field, then rot is a meaningful expression.

98. If is a vector field and then is irrotational but

not conservative.

F

rot F 0,

F

f

f

y

y

x, y

F x, y 4xi y 2 j

x, y → 0, 0 .

F x, y → 0

F x, y 4xi y 2 j,

f n nf n 2 F.

1

f

F

f 3.

ln f

F

f 2.

fx, y, z F x, y, z .

F x, y, z

xi yj zk,

div rot F 0

div f F f div F f F

f F f F f F

f F F

div F G rot F G F rot G

div F G div F div G

rot f f 0

rot F G rot F rot G

f.

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

div rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

div F G F G .

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

F G F G .

3, 2, 1

F x, y, z ln xyz i j k

3, 0, 0

F x, y, z e x sen yi e x cos yj z 2 k

2, 1, 3

F x, y, z x 2 zi 2xzj yzk

2, 1, 1

F x, y, z xyzi xyj zk

Punto

Campo vectorial

F x, y, z ln x 2 y 2 i xyj ln y 2 z 2 k

F x, y, z senxi cos yj z 2 k

F x, y xe x i ye y j

F x, y x 2 i 2y 2 j

F x, y, z

x

x 2 y 2 i y

x 2 y 2 j k

F x, y, z

z

y i

xz

y 2 j

x

y k

F x, y, z ye z i ze x j xe y k

F x, y, z sen zi sen xj sen yk

F x, y, z y 2 z 3 i 2xyz 3 j 3xy 2 z 2 k

F x, y, z xy 2 z 2 i x 2 yz 2 j x 2 y 2 zk

F x, y, z x 2 y 2 z 2 i j k

F x, y, z sen x y i sen y z j sen z x k

F x, y, z

yz

y z i xz

x z j xy

x

y k

F x, y, z arctan x y i ln x2 y 2 j k

1068 Chapter 15 Vector Analysis

CAS

71. Define a vector field in the plane and in space. Give some

physical examples of vector fields.

72. What is a conservative vector field, and how do you test for

it in the plane and in space?

73. Define the rot of a vector field.

74. Define the divergence of a vector field in the plane and in

space.

WRITING ABOUT CONCEPTS

94. (a) Sketch several representative vectors in the vector field

given by

(b) Sketch several representative vectors in the vector field

given by

(c) Explain any similarities or differences in the vector

fields y G x, y .

F x, y

G x, y

xi

yj

x 2 y 2.

F x, y

xi

yj

x 2 y 2.

CAPSTONE

In Exercises 53–56, use a computer algebra system to find the

rot F for the vector field.

53.

54.

55.

56.

In Exercises 57–62, determine whether the vector field F is

conservative. If it is, find a potential function for the vector field.

57.

58.

59.

60.

61.

62.

In Exercises 63–66, find the divergence of the vector field F.

63.

64.

65.

66.

In Exercises 67–70, find the divergence of the vector field F at

the given point.

67.

68.

69.

70.

In Exercises 75 and 76, find rot

75. 76.

In Exercises 77 and 78, find rot

77.

78.

In Exercises 79 and 80, find

79. 80.

In Exercises 81 and 82, find

81.

82.

In Exercises 83–90, prove the property for vector fields F and G

and scalar function

(Assume that the required partial

derivatives are continuous.)

83.

84.

85.

86.

87.

88.

89.

90. (Theorem 15.3)

In Exercises 91–93, let

and let

91. Show that 92. Show that

93. Show that

True or False?

In Exercises 95–98, determine whether the

statement is true or false. If it is false, explain why or give an

example that shows it is false.

95. If then as

96. If and is on the positive -axis, then

the vector points in the negative -direction.

97. If is a scalar field, then rot is a meaningful expression.

98. If is a vector field and then is irrotational but

not conservative.

F

rot F 0,

F

f

f

y

y

x, y

F x, y 4xi y 2 j

x, y → 0, 0 .

F x, y → 0

F x, y 4xi y 2 j,

f n nf n 2 F.

1

f

F

f 3.

ln f

F

f 2.

fx, y, z F x, y, z .

F x, y, z

xi yj zk,

div rot F 0

div f F f div F f F

f F f F f F

f F F

div F G rot F G F rot G

div F G div F div G

rot f f 0

rot F G rot F rot G

f.

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

div rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

div F G F G .

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

F G F G .

3, 2, 1

F x, y, z ln xyz i j k

3, 0, 0

F x, y, z e x sen yi e x cos yj z 2 k

2, 1, 3

F x, y, z x 2 zi 2xzj yzk

2, 1, 1

F x, y, z xyzi xyj zk

Punto

Campo vectorial

F x, y, z ln x 2 y 2 i xyj ln y 2 z 2 k

F x, y, z senxi cos yj z 2 k

F x, y xe x i ye y j

F x, y x 2 i 2y 2 j

F x, y, z

x

x 2 y 2 i y

x 2 y 2 j k

F x, y, z

z

y i

xz

y 2 j

x

y k

F x, y, z ye z i ze x j xe y k

F x, y, z sen zi sen xj sen yk

F x, y, z y 2 z 3 i 2xyz 3 j 3xy 2 z 2 k

F x, y, z xy 2 z 2 i x 2 yz 2 j x 2 y 2 zk

F x, y, z x 2 y 2 z 2 i j k

F x, y, z sen x y i sen y z j sen z x k

F x, y, z

yz

y z i xz

x z j xy

x

y k

F x, y, z arctan x y i ln x2 y 2 j k

1068 Chapter 15 Vector Analysis

CAS

71. Define a vector field in the plane and in space. Give some

physical examples of vector fields.

72. What is a conservative vector field, and how do you test for

it in the plane and in space?

73. Define the rot of a vector field.

74. Define the divergence of a vector field in the plane and in

space.

WRITING ABOUT CONCEPTS

94. (a) Sketch several representative vectors in the vector field

given by

(b) Sketch several representative vectors in the vector field

given by

(c) Explain any similarities or differences in the vector

fields y G x, y .

F x, y

G x, y

xi

yj

x 2 y 2.

F x, y

xi

yj

x 2 y 2.

CAPSTONE

In Exercises 53–56, use a computer algebra system to find the

rot F for the vector field.

53.

54.

55.

56.

In Exercises 57–62, determine whether the vector field F is

conservative. If it is, find a potential function for the vector field.

57.

58.

59.

60.

61.

62.

In Exercises 63–66, find the divergence of the vector field F.

63.

64.

65.

66.

In Exercises 67–70, find the divergence of the vector field F at

the given point.

67.

68.

69.

70.

In Exercises 75 and 76, find rot

75. 76.

In Exercises 77 and 78, find rot

77.

78.

In Exercises 79 and 80, find

79. 80.

In Exercises 81 and 82, find

81.

82.

In Exercises 83–90, prove the property for vector fields F and G

and scalar function

(Assume that the required partial

derivatives are continuous.)

83.

84.

85.

86.

87.

88.

89.

90. (Theorem 15.3)

In Exercises 91–93, let

and let

91. Show that 92. Show that

93. Show that

True or False?

In Exercises 95–98, determine whether the

statement is true or false. If it is false, explain why or give an

example that shows it is false.

95. If then as

96. If and is on the positive -axis, then

the vector points in the negative -direction.

97. If is a scalar field, then rot is a meaningful expression.

98. If is a vector field and then is irrotational but

not conservative.

F

rot F 0,

F

f

f

y

y

x, y

F x, y 4xi y 2 j

x, y → 0, 0 .

F x, y → 0

F x, y 4xi y 2 j,

f n nf n 2 F.

1

f

F

f 3.

ln f

F

f 2.

fx, y, z F x, y, z .

F x, y, z

xi yj zk,

div rot F 0

div f F f div F f F

f F f F f F

f F F

div F G rot F G F rot G

div F G div F div G

rot f f 0

rot F G rot F rot G

f.

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

div rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

div F G F G .

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

F G F G .

3, 2, 1

F x, y, z ln xyz i j k

3, 0, 0

F x, y, z e x sen yi e x cos yj z 2 k

2, 1, 3

F x, y, z x 2 zi 2xzj yzk

2, 1, 1

F x, y, z xyzi xyj zk

Punto

Campo vectorial

F x, y, z ln x 2 y 2 i xyj ln y 2 z 2 k

F x, y, z senxi cos yj z 2 k

F x, y xe x i ye y j

F x, y x 2 i 2y 2 j

F x, y, z

x

x 2 y 2 i y

x 2 y 2 j k

F x, y, z

z

y i

xz

y 2 j

x

y k

F x, y, z ye z i ze x j xe y k

F x, y, z sen zi sen xj sen yk

F x, y, z y 2 z 3 i 2xyz 3 j 3xy 2 z 2 k

F x, y, z xy 2 z 2 i x 2 yz 2 j x 2 y 2 zk

F x, y, z x 2 y 2 z 2 i j k

F x, y, z sen x y i sen y z j sen z x k

F x, y, z

yz

y z i xz

x z j xy

x

y k

F x, y, z arctan x y i ln x2 y 2 j k

1068 Chapter 15 Vector Analysis

CAS

71. Define a vector field in the plane and in space. Give some

physical examples of vector fields.

72. What is a conservative vector field, and how do you test for

it in the plane and in space?

73. Define the rot of a vector field.

74. Define the divergence of a vector field in the plane and in

space.

WRITING ABOUT CONCEPTS

94. (a) Sketch several representative vectors in the vector field

given by

(b) Sketch several representative vectors in the vector field

given by

(c) Explain any similarities or differences in the vector

fields y G x, y .

F x, y

G x, y

xi

yj

x 2 y 2.

F x, y

xi

yj

x 2 y 2.

CAPSTONE

In Exercises 53–56, use a computer algebra system to find the

rot F for the vector field.

53.

54.

55.

56.

In Exercises 57–62, determine whether the vector field F is

conservative. If it is, find a potential function for the vector field.

57.

58.

59.

60.

61.

62.

In Exercises 63–66, find the divergence of the vector field F.

63.

64.

65.

66.

In Exercises 67–70, find the divergence of the vector field F at

the given point.

67.

68.

69.

70.

In Exercises 75 and 76, find rot

75. 76.

In Exercises 77 and 78, find rot

77.

78.

In Exercises 79 and 80, find

79. 80.

In Exercises 81 and 82, find

81.

82.

In Exercises 83–90, prove the property for vector fields F and G

and scalar function

(Assume that the required partial

derivatives are continuous.)

83.

84.

85.

86.

87.

88.

89.

90. (Theorem 15.3)

In Exercises 91–93, let

and let

91. Show that 92. Show that

93. Show that

True or False?

In Exercises 95–98, determine whether the

statement is true or false. If it is false, explain why or give an

example that shows it is false.

95. If then as

96. If and is on the positive -axis, then

the vector points in the negative -direction.

97. If is a scalar field, then rot is a meaningful expression.

98. If is a vector field and then is irrotational but

not conservative.

F

rot F 0,

F

f

f

y

y

x, y

F x, y 4xi y 2 j

x, y → 0, 0 .

F x, y → 0

F x, y 4xi y 2 j,

f n nf n 2 F.

1

f

F

f 3.

ln f

F

f 2.

fx, y, z F x, y, z .

F x, y, z

xi yj zk,

div rot F 0

div f F f div F f F

f F f F f F

f F F

div F G rot F G F rot G

div F G div F div G

rot f f 0

rot F G rot F rot G

f.

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

div rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

div F G F G .

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

F G F G .

3, 2, 1

F x, y, z ln xyz i j k

3, 0, 0

F x, y, z e x sen yi e x cos yj z 2 k

2, 1, 3

F x, y, z x 2 zi 2xzj yzk

2, 1, 1

F x, y, z xyzi xyj zk

Punto

Campo vectorial

F x, y, z ln x 2 y 2 i xyj ln y 2 z 2 k

F x, y, z senxi cos yj z 2 k

F x, y xe x i ye y j

F x, y x 2 i 2y 2 j

F x, y, z

x

x 2 y 2 i y

x 2 y 2 j k

F x, y, z

z

y i

xz

y 2 j

x

y k

F x, y, z ye z i ze x j xe y k

F x, y, z sen zi sen xj sen yk

F x, y, z y 2 z 3 i 2xyz 3 j 3xy 2 z 2 k

F x, y, z xy 2 z 2 i x 2 yz 2 j x 2 y 2 zk

F x, y, z x 2 y 2 z 2 i j k

F x, y, z sen x y i sen y z j sen z x k

F x, y, z

yz

y z i xz

x z j xy

x

y k

F x, y, z arctan x y i ln x2 y 2 j k

1068 Chapter 15 Vector Analysis

CAS

71. Define a vector field in the plane and in space. Give some

physical examples of vector fields.

72. What is a conservative vector field, and how do you test for

it in the plane and in space?

73. Define the rot of a vector field.

74. Define the divergence of a vector field in the plane and in

space.

WRITING ABOUT CONCEPTS

94. (a) Sketch several representative vectors in the vector field

given by

(b) Sketch several representative vectors in the vector field

given by

(c) Explain any similarities or differences in the vector

fields y G x, y .

F x, y

G x, y

xi

yj

x 2 y 2.

F x, y

xi

yj

x 2 y 2.

CAPSTONE

In Exercises 53–56, use a computer algebra system to find the

rot F for the vector field.

53.

54.

55.

56.

In Exercises 57–62, determine whether the vector field F is

conservative. If it is, find a potential function for the vector field.

57.

58.

59.

60.

61.

62.

In Exercises 63–66, find the divergence of the vector field F.

63.

64.

65.

66.

In Exercises 67–70, find the divergence of the vector field F at

the given point.

67.

68.

69.

70.

In Exercises 75 and 76, find rot

75. 76.

In Exercises 77 and 78, find rot

77.

78.

In Exercises 79 and 80, find

79. 80.

In Exercises 81 and 82, find

81.

82.

In Exercises 83–90, prove the property for vector fields F and G

and scalar function

(Assume that the required partial

derivatives are continuous.)

83.

84.

85.

86.

87.

88.

89.

90. (Theorem 15.3)

In Exercises 91–93, let

and let

91. Show that 92. Show that

93. Show that

True or False?

In Exercises 95–98, determine whether the

statement is true or false. If it is false, explain why or give an

example that shows it is false.

95. If then as

96. If and is on the positive -axis, then

the vector points in the negative -direction.

97. If is a scalar field, then rot is a meaningful expression.

98. If is a vector field and then is irrotational but

not conservative.

F

rot F 0,

F

f

f

y

y

x, y

F x, y 4xi y 2 j

x, y → 0, 0 .

F x, y → 0

F x, y 4xi y 2 j,

f n nf n 2 F.

1

f

F

f 3.

ln f

F

f 2.

fx, y, z F x, y, z .

F x, y, z

xi yj zk,

div rot F 0

div f F f div F f F

f F f F f F

f F F

div F G rot F G F rot G

div F G div F div G

rot f f 0

rot F G rot F rot G

f.

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

div rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

div F G F G .

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

F G F G .

3, 2, 1

F x, y, z ln xyz i j k

3, 0, 0

F x, y, z e x sen yi e x cos yj z 2 k

2, 1, 3

F x, y, z x 2 zi 2xzj yzk

2, 1, 1

F x, y, z xyzi xyj zk

Punto

Campo vectorial

F x, y, z ln x 2 y 2 i xyj ln y 2 z 2 k

F x, y, z senxi cos yj z 2 k

F x, y xe x i ye y j

F x, y x 2 i 2y 2 j

F x, y, z

x

x 2 y 2 i y

x 2 y 2 j k

F x, y, z

z

y i

xz

y 2 j

x

y k

F x, y, z ye z i ze x j xe y k

F x, y, z sen zi sen xj sen yk

F x, y, z y 2 z 3 i 2xyz 3 j 3xy 2 z 2 k

F x, y, z xy 2 z 2 i x 2 yz 2 j x 2 y 2 zk

F x, y, z x 2 y 2 z 2 i j k

F x, y, z sen x y i sen y z j sen z x k

F x, y, z

yz

y z i xz

x z j xy

x

y k

F x, y, z arctan x y i ln x2 y 2 j k

1068 Chapter 15 Vector Analysis

CAS

71. Define a vector field in the plane and in space. Give some

physical examples of vector fields.

72. What is a conservative vector field, and how do you test for

it in the plane and in space?

73. Define the rot of a vector field.

74. Define the divergence of a vector field in the plane and in

space.

WRITING ABOUT CONCEPTS

94. (a) Sketch several representative vectors in the vector field

given by

(b) Sketch several representative vectors in the vector field

given by

(c) Explain any similarities or differences in the vector

fields y G x, y .

F x, y

G x, y

xi

yj

x 2 y 2.

F x, y

xi

yj

x 2 y 2.

CAPSTONE

Para discusión

94. a) Dibujar varios vectores representativos en el campo vectorial

dado por

b) Dibujar varios vectores representativos en el campo vectorial

dado por

c) Explicar cualquier similitud o diferencia en los campos

vectoriales

In Exercises 53–56, use a computer algebra system to find the

rot F for the vector field.

53.

54.

55.

56.

In Exercises 57–62, determine whether the vector field F is

conservative. If it is, find a potential function for the vector field.

57.

58.

59.

60.

61.

62.

In Exercises 63–66, find the divergence of the vector field F.

63.

64.

65.

66.

In Exercises 67–70, find the divergence of the vector field F at

the given point.

67.

68.

69.

70.

In Exercises 75 and 76, find rot

75. 76.

In Exercises 77 and 78, find rot

77.

78.

In Exercises 79 and 80, find

79. 80.

In Exercises 81 and 82, find

81.

82.

In Exercises 83–90, prove the property for vector fields F and G

and scalar function

(Assume that the required partial

derivatives are continuous.)

83.

84.

85.

86.

87.

88.

89.

90. (Theorem 15.3)

In Exercises 91–93, let

and let

91. Show that 92. Show that

93. Show that

True or False?

In Exercises 95–98, determine whether the

statement is true or false. If it is false, explain why or give an

example that shows it is false.

95. If then as

96. If and is on the positive -axis, then

the vector points in the negative -direction.

97. If is a scalar field, then rot is a meaningful expression.

98. If is a vector field and then is irrotational but

not conservative.

F

rot F 0,

F

f

f

y

y

x, y

F x, y 4xi y 2 j

x, y → 0, 0 .

F x, y → 0

F x, y 4xi y 2 j,

f n nf n 2 F.

1

f

F

f 3.

ln f

F

f 2.

fx, y, z F x, y, z .

F x, y, z

xi yj zk,

div rot F 0

div f F f div F f F

f F f F f F

f F F

div F G rot F G F rot G

div F G div F div G

rot f f 0

rot F G rot F rot G

f.

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

div rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

div F G F G .

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

F G F G .

3, 2, 1

F x, y, z ln xyz i j k

3, 0, 0

F x, y, z e x sen yi e x cos yj z 2 k

2, 1, 3

F x, y, z x 2 zi 2xzj yzk

2, 1, 1

F x, y, z xyzi xyj zk

Punto

Campo vectorial

F x, y, z ln x 2 y 2 i xyj ln y 2 z 2 k

F x, y, z senxi cos yj z 2 k

F x, y xe x i ye y j

F x, y x 2 i 2y 2 j

F x, y, z

x

x 2 y 2 i y

x 2 y 2 j k

F x, y, z

z

y i

xz

y 2 j

x

y k

F x, y, z ye z i ze x j xe y k

F x, y, z sen zi sen xj sen yk

F x, y, z y 2 z 3 i 2xyz 3 j 3xy 2 z 2 k

F x, y, z xy 2 z 2 i x 2 yz 2 j x 2 y 2 zk

F x, y, z x 2 y 2 z 2 i j k

F x, y, z sen x y i sen y z j sen z x k

F x, y, z

yz

y z i xz

x z j xy

x

y k

F x, y, z arctan x y i ln x2 y 2 j k

1068 Chapter 15 Vector Analysis

CAS

71. Define a vector field in the plane and in space. Give some

physical examples of vector fields.

72. What is a conservative vector field, and how do you test for

it in the plane and in space?

73. Define the rot of a vector field.

74. Define the divergence of a vector field in the plane and in

space.

WRITING ABOUT CONCEPTS

94. (a) Sketch several representative vectors in the vector field

given by

(b) Sketch several representative vectors in the vector field

given by

(c) Explain any similarities or differences in the vector

fields y G x, y .

F x, y

G x, y

xi

yj

x 2 y 2.

F x, y

xi

yj

x 2 y 2.

CAPSTONE

In Exercises 53–56, use a computer algebra system to find the

rot F for the vector field.

53.

54.

55.

56.

In Exercises 57–62, determine whether the vector field F is

conservative. If it is, find a potential function for the vector field.

57.

58.

59.

60.

61.

62.

In Exercises 63–66, find the divergence of the vector field F.

63.

64.

65.

66.

In Exercises 67–70, find the divergence of the vector field F at

the given point.

67.

68.

69.

70.

In Exercises 75 and 76, find rot

75. 76.

In Exercises 77 and 78, find rot

77.

78.

In Exercises 79 and 80, find

79. 80.

In Exercises 81 and 82, find

81.

82.

In Exercises 83–90, prove the property for vector fields F and G

and scalar function

(Assume that the required partial

derivatives are continuous.)

83.

84.

85.

86.

87.

88.

89.

90. (Theorem 15.3)

In Exercises 91–93, let

and let

91. Show that 92. Show that

93. Show that

True or False?

In Exercises 95–98, determine whether the

statement is true or false. If it is false, explain why or give an

example that shows it is false.

95. If then as

96. If and is on the positive -axis, then

the vector points in the negative -direction.

97. If is a scalar field, then rot is a meaningful expression.

98. If is a vector field and then is irrotational but

not conservative.

F

rot F 0,

F

f

f

y

y

x, y

F x, y 4xi y 2 j

x, y → 0, 0 .

F x, y → 0

F x, y 4xi y 2 j,

f n nf n 2 F.

1

f

F

f 3.

ln f

F

f 2.

fx, y, z F x, y, z .

F x, y, z

xi yj zk,

div rot F 0

div f F f div F f F

f F f F f F

f F F

div F G rot F G F rot G

div F G div F div G

rot f f 0

rot F G rot F rot G

f.

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

div rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

div F G F G .

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

F G F G .

3, 2, 1

F x, y, z ln xyz i j k

3, 0, 0

F x, y, z e x sen yi e x cos yj z 2 k

2, 1, 3

F x, y, z x 2 zi 2xzj yzk

2, 1, 1

F x, y, z xyzi xyj zk

Punto

Campo vectorial

F x, y, z ln x 2 y 2 i xyj ln y 2 z 2 k

F x, y, z senxi cos yj z 2 k

F x, y xe x i ye y j

F x, y x 2 i 2y 2 j

F x, y, z

x

x 2 y 2 i y

x 2 y 2 j k

F x, y, z

z

y i

xz

y 2 j

x

y k

F x, y, z ye z i ze x j xe y k

F x, y, z sen zi sen xj sen yk

F x, y, z y 2 z 3 i 2xyz 3 j 3xy 2 z 2 k

F x, y, z xy 2 z 2 i x 2 yz 2 j x 2 y 2 zk

F x, y, z x 2 y 2 z 2 i j k

F x, y, z sen x y i sen y z j sen z x k

F x, y, z

yz

y z i xz

x z j xy

x

y k

F x, y, z arctan x y i ln x2 y 2 j k

1068 Chapter 15 Vector Analysis

CAS

71. Define a vector field in the plane and in space. Give some

physical examples of vector fields.

72. What is a conservative vector field, and how do you test for

it in the plane and in space?

73. Define the rot of a vector field.

74. Define the divergence of a vector field in the plane and in

space.

WRITING ABOUT CONCEPTS

94. (a) Sketch several representative vectors in the vector field

given by

(b) Sketch several representative vectors in the vector field

given by

(c) Explain any similarities or differences in the vector

fields y G x, y .

F x, y

G x, y

xi

yj

x 2 y 2.

F x, y

xi

yj

x 2 y 2.

CAPSTONE

In Exercises 53–56, use a computer algebra system to find the

rot F for the vector field.

53.

54.

55.

56.

In Exercises 57–62, determine whether the vector field F is

conservative. If it is, find a potential function for the vector field.

57.

58.

59.

60.

61.

62.

In Exercises 63–66, find the divergence of the vector field F.

63.

64.

65.

66.

In Exercises 67–70, find the divergence of the vector field F at

the given point.

67.

68.

69.

70.

In Exercises 75 and 76, find rot

75. 76.

In Exercises 77 and 78, find rot

77.

78.

In Exercises 79 and 80, find

79. 80.

In Exercises 81 and 82, find

81.

82.

In Exercises 83–90, prove the property for vector fields F and G

and scalar function

(Assume that the required partial

derivatives are continuous.)

83.

84.

85.

86.

87.

88.

89.

90. (Theorem 15.3)

In Exercises 91–93, let

and let

91. Show that 92. Show that

93. Show that

True or False?

In Exercises 95–98, determine whether the

statement is true or false. If it is false, explain why or give an

example that shows it is false.

95. If then as

96. If and is on the positive -axis, then

the vector points in the negative -direction.

97. If is a scalar field, then rot is a meaningful expression.

98. If is a vector field and then is irrotational but

not conservative.

F

rot F 0,

F

f

f

y

y

x, y

F x, y 4xi y 2 j

x, y → 0, 0 .

F x, y → 0

F x, y 4xi y 2 j,

f n nf n 2 F.

1

f

F

f 3.

ln f

F

f 2.

fx, y, z F x, y, z .

F x, y, z

xi yj zk,

div rot F 0

div f F f div F f F

f F f F f F

f F F

div F G rot F G F rot G

div F G div F div G

rot f f 0

rot F G rot F rot G

f.

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

div rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

div F G F G .

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

F G F G .

3, 2, 1

F x, y, z ln xyz i j k

3, 0, 0

F x, y, z e x sen yi e x cos yj z 2 k

2, 1, 3

F x, y, z x 2 zi 2xzj yzk

2, 1, 1

F x, y, z xyzi xyj zk

Punto

Campo vectorial

F x, y, z ln x 2 y 2 i xyj ln y 2 z 2 k

F x, y, z senxi cos yj z 2 k

F x, y xe x i ye y j

F x, y x 2 i 2y 2 j

F x, y, z

x

x 2 y 2 i y

x 2 y 2 j k

F x, y, z

z

y i

xz

y 2 j

x

y k

F x, y, z ye z i ze x j xe y k

F x, y, z sen zi sen xj sen yk

F x, y, z y 2 z 3 i 2xyz 3 j 3xy 2 z 2 k

F x, y, z xy 2 z 2 i x 2 yz 2 j x 2 y 2 zk

F x, y, z x 2 y 2 z 2 i j k

F x, y, z sen x y i sen y z j sen z x k

F x, y, z

yz

y z i xz

x z j xy

x

y k

F x, y, z arctan x y i ln x2 y 2 j k

1068 Chapter 15 Vector Analysis

CAS

71. Define a vector field in the plane and in space. Give some

physical examples of vector fields.

72. What is a conservative vector field, and how do you test for

it in the plane and in space?

73. Define the rot of a vector field.

74. Define the divergence of a vector field in the plane and in

space.

WRITING ABOUT CONCEPTS

94. (a) Sketch several representative vectors in the vector field

given by

(b) Sketch several representative vectors in the vector field

given by

(c) Explain any similarities or differences in the vector

fields y G x, y .

F x, y

G x, y

xi

yj

x 2 y 2.

F x, y

xi

yj

x 2 y 2.

CAPSTONE

In Exercises 53–56, use a computer algebra system to find the

rot F for the vector field.

53.

54.

55.

56.

In Exercises 57–62, determine whether the vector field F is

conservative. If it is, find a potential function for the vector field.

57.

58.

59.

60.

61.

62.

In Exercises 63–66, find the divergence of the vector field F.

63.

64.

65.

66.

In Exercises 67–70, find the divergence of the vector field F at

the given point.

67.

68.

69.

70.

In Exercises 75 and 76, find rot

75. 76.

In Exercises 77 and 78, find rot

77.

78.

In Exercises 79 and 80, find

79. 80.

In Exercises 81 and 82, find

81.

82.

In Exercises 83–90, prove the property for vector fields F and G

and scalar function

(Assume that the required partial

derivatives are continuous.)

83.

84.

85.

86.

87.

88.

89.

90. (Theorem 15.3)

In Exercises 91–93, let

and let

91. Show that 92. Show that

93. Show that

True or False?

In Exercises 95–98, determine whether the

statement is true or false. If it is false, explain why or give an

example that shows it is false.

95. If then as

96. If and is on the positive -axis, then

the vector points in the negative -direction.

97. If is a scalar field, then rot is a meaningful expression.

98. If is a vector field and then is irrotational but

not conservative.

F

rot F 0,

F

f

f

y

y

x, y

F x, y 4xi y 2 j

x, y → 0, 0 .

F x, y → 0

F x, y 4xi y 2 j,

f n nf n 2 F.

1

f

F

f 3.

ln f

F

f 2.

fx, y, z F x, y, z .

F x, y, z

xi yj zk,

div rot F 0

div f F f div F f F

f F f F f F

f F F

div F G rot F G F rot G

div F G div F div G

rot f f 0

rot F G rot F rot G

f.

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

div rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

div F G F G .

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

F G F G .

3, 2, 1

F x, y, z ln xyz i j k

3, 0, 0

F x, y, z e x sen yi e x cos yj z 2 k

2, 1, 3

F x, y, z x 2 zi 2xzj yzk

2, 1, 1

F x, y, z xyzi xyj zk

Punto

Campo vectorial

F x, y, z ln x 2 y 2 i xyj ln y 2 z 2 k

F x, y, z senxi cos yj z 2 k

F x, y xe x i ye y j

F x, y x 2 i 2y 2 j

F x, y, z

x

x 2 y 2 i y

x 2 y 2 j k

F x, y, z

z

y i

xz

y 2 j

x

y k

F x, y, z ye z i ze x j xe y k

F x, y, z sen zi sen xj sen yk

F x, y, z y 2 z 3 i 2xyz 3 j 3xy 2 z 2 k

F x, y, z xy 2 z 2 i x 2 yz 2 j x 2 y 2 zk

F x, y, z x 2 y 2 z 2 i j k

F x, y, z sen x y i sen y z j sen z x k

F x, y, z

yz

y z i xz

x z j xy

x

y k

F x, y, z arctan x y i ln x2 y 2 j k

1068 Chapter 15 Vector Analysis

CAS

71. Define a vector field in the plane and in space. Give some

physical examples of vector fields.

72. What is a conservative vector field, and how do you test for

it in the plane and in space?

73. Define the rot of a vector field.

74. Define the divergence of a vector field in the plane and in

space.

WRITING ABOUT CONCEPTS

94. (a) Sketch several representative vectors in the vector field

given by

(b) Sketch several representative vectors in the vector field

given by

(c) Explain any similarities or differences in the vector

fields y G x, y .

F x, y

G x, y

xi

yj

x 2 y 2.

F x, y

xi

yj

x 2 y 2.

CAPSTONE

In Exercises 53–56, use a computer algebra system to find the

rot F for the vector field.

53.

54.

55.

56.

In Exercises 57–62, determine whether the vector field F is

conservative. If it is, find a potential function for the vector field.

57.

58.

59.

60.

61.

62.

In Exercises 63–66, find the divergence of the vector field F.

63.

64.

65.

66.

In Exercises 67–70, find the divergence of the vector field F at

the given point.

67.

68.

69.

70.

In Exercises 75 and 76, find rot

75. 76.

In Exercises 77 and 78, find rot

77.

78.

In Exercises 79 and 80, find

79. 80.

In Exercises 81 and 82, find

81.

82.

In Exercises 83–90, prove the property for vector fields F and G

and scalar function

(Assume that the required partial

derivatives are continuous.)

83.

84.

85.

86.

87.

88.

89.

90. (Theorem 15.3)

In Exercises 91–93, let

and let

91. Show that 92. Show that

93. Show that

True or False?

In Exercises 95–98, determine whether the

statement is true or false. If it is false, explain why or give an

example that shows it is false.

95. If then as

96. If and is on the positive -axis, then

the vector points in the negative -direction.

97. If is a scalar field, then rot is a meaningful expression.

98. If is a vector field and then is irrotational but

not conservative.

F

rot F 0,

F

f

f

y

y

x, y

F x, y 4xi y 2 j

x, y → 0, 0 .

F x, y → 0

F x, y 4xi y 2 j,

f n nf n 2 F.

1

f

F

f 3.

ln f

F

f 2.

fx, y, z F x, y, z .

F x, y, z

xi yj zk,

div rot F 0

div f F f div F f F

f F f F f F

f F F

div F G rot F G F rot G

div F G div F div G

rot f f 0

rot F G rot F rot G

f.

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

div rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

div F G F G .

F x, y, z x 2 zi 2xzj yzk

F x, y, z xyzi yj zk

rot F F .

G x, y, z x 2 i yj z 2 k

G x, y, z xi yj zk

F x, y, z xi zk

F x, y, z i 3xj 2yk

F G F G .

3, 2, 1

F x, y, z ln xyz i j k

3, 0, 0

F x, y, z e x sen yi e x cos yj z 2 k

2, 1, 3

F x, y, z x 2 zi 2xzj yzk

2, 1, 1

F x, y, z xyzi xyj zk

Punto

Campo vectorial

F x, y, z ln x 2 y 2 i xyj ln y 2 z 2 k

F x, y, z senxi cos yj z 2 k

F x, y xe x i ye y j

F x, y x 2 i 2y 2 j

F x, y, z

x

x 2 y 2 i y

x 2 y 2 j k

F x, y, z

z

y i

xz

y 2 j

x

y k

F x, y, z ye z i ze x j xe y k

F x, y, z sen zi sen xj sen yk

F x, y, z y 2 z 3 i 2xyz 3 j 3xy 2 z 2 k

F x, y, z xy 2 z 2 i x 2 yz 2 j x 2 y 2 zk

F x, y, z x 2 y 2 z 2 i j k

F x, y, z sen x y i sen y z j sen z x k

F x, y, z

yz

y z i xz

x z j xy

x

y k

F x, y, z arctan x y i ln x2 y 2 j k

1068 Chapter 15 Vector Analysis

CAS

71. Define a vector field in the plane and in space. Give some

physical examples of vector fields.

72. What is a conservative vector field, and how do you test for

it in the plane and in space?

73. Define the rot of a vector field.

74. Define the divergence of a vector field in the plane and in

space.

WRITING ABOUT CONCEPTS

94. (a) Sketch several representative vectors in the vector field

given by

(b) Sketch several representative vectors in the vector field

given by

(c) Explain any similarities or differences in the vector

fields y G x, y .

F x, y

G x, y

xi

yj

x 2 y 2.

F x, y

xi

yj

x 2 y 2.

CAPSTONE

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