Problem Set 60: Polar Coordinates: Graphs

1. Describe the three types of symmetry in polar graphs, and compare them to the symmetry of the Cartesian plane.

2. Which of the three types of symmetries for polar graphs correspond to the symmetries with respect to the x-axis, y-axis, and origin?

3. What are the steps to follow when graphing polar equations?

4. Describe the shapes of the graphs of cardioids, limaçons, and lemniscates.

5. What part of the equation determines the shape of the graph of a polar equation?

For the following exercises, test the equation for symmetry.

6. r=5cos3θr=5cos3θ

7. r=33cosθr=33cosθ

8. r=3+2sinθr=3+2sinθ

9. r=3sin2θr=3sin2θ

10. r=4r=4

11. r=2θr=2θ

12. r=4cosθ2r=4cosθ2

13. r=2θr=2θ

14. r=31cos2θr=31cos2θ

15. r=5sin2θr=5sin2θ

For the following exercises, graph the polar equation. Identify the name of the shape.

16. r=3cosθr=3cosθ

17. r=4sinθr=4sinθ

18. r=2+2cosθr=2+2cosθ

19. r=22cosθr=22cosθ

20. r=55sinθr=55sinθ

21. r=3+3sinθr=3+3sinθ

22. r=3+2sinθr=3+2sinθ

23. r=7+4sinθr=7+4sinθ

24. r=4+3cosθr=4+3cosθ

25. r=5+4cosθr=5+4cosθ

26. r=10+9cosθr=10+9cosθ

27. r=1+3sinθr=1+3sinθ

28. r=2+5sinθr=2+5sinθ

29. r=5+7sinθr=5+7sinθ

30. r=2+4cosθr=2+4cosθ

31. r=5+6cosθr=5+6cosθ

32. r2=36cos(2θ)r2=36cos(2θ)

33. r2=10cos(2θ)r2=10cos(2θ)

34. r2=4sin(2θ)r2=4sin(2θ)

35. r2=10sin(2θ)r2=10sin(2θ)

36. r=3sin(2θ)r=3sin(2θ)

37. r=3cos(2θ)r=3cos(2θ)

38. r=5sin(3θ)r=5sin(3θ)

39. r=4sin(4θ)r=4sin(4θ)

40. r=4sin(5θ)r=4sin(5θ)

41. r=θr=θ

42. r=2θr=2θ

43. r=3θr=3θ

For the following exercises, use a graphing calculator to sketch the graph of the polar equation.

44. r=1θr=1θ

45. r=1θr=1θ

46. r=2sinθtanθr=2sinθtanθ, a cissoid

47. r=21sin2θr=21sin2θ , a hippopede

48. r=5+cos(4θ)r=5+cos(4θ)

49. r=2sin(2θ)r=2sin(2θ)

50. r=θ2r=θ2

51. r=θ+1r=θ+1

52. r=θsinθr=θsinθ

53. r=θcosθr=θcosθ

For the following exercises, use a graphing utility to graph each pair of polar equations on a domain of [0,4π][0,4π] and then explain the differences shown in the graphs.

54. r=θ,r=θr=θ,r=θ

55. r=θ,r=θ+sinθr=θ,r=θ+sinθ

56. r=sinθ+θ,r=sinθθr=sinθ+θ,r=sinθθ

57. r=2sin(θ2),r=θsin(θ2)r=2sin(θ2),r=θsin(θ2)

58. r=sin(cos(3θ))r=sin(3θ)r=sin(cos(3θ))r=sin(3θ)

59. On a graphing utility, graph r=sin(165θ)r=sin(165θ) on [0,4π],[0,8π],[0,12π][0,4π],[0,8π],[0,12π], and [0,16π][0,16π]. Describe the effect of increasing the width of the domain.

60. On a graphing utility, graph and sketch r=sinθ+(sin(52θ))3r=sinθ+(sin(52θ))3 on [0,4π][0,4π].

61. On a graphing utility, graph each polar equation. Explain the similarities and differences you observe in the graphs.
r1=3sin(3θ)r2=2sin(3θ)r3=sin(3θ)r1=3sin(3θ)r2=2sin(3θ)r3=sin(3θ)

62. On a graphing utility, graph each polar equation. Explain the similarities and differences you observe in the graphs.
r1=3+3cosθr2=2+2cosθr3=1+cosθr1=3+3cosθr2=2+2cosθr3=1+cosθ

63. On a graphing utility, graph each polar equation. Explain the similarities and differences you observe in the graphs.
r1=3θr2=2θr3=θr1=3θr2=2θr3=θ

For the following exercises, draw each polar equation on the same set of polar axes, and find the points of intersection.

64. r1=3+2sinθ,r2=2r1=3+2sinθ,r2=2

65. r1=64cosθ,r2=4r1=64cosθ,r2=4

66. r1=1+sinθ,r2=3sinθr1=1+sinθ,r2=3sinθ

67. r1=1+cosθ,r2=3cosθr1=1+cosθ,r2=3cosθ

68. r1=cos(2θ),r2=sin(2θ)r1=cos(2θ),r2=sin(2θ)

69. r1=sin2(2θ),r2=1cos(4θ)r1=sin2(2θ),r2=1cos(4θ)

70. r1=3,r2=2sin(θ)r1=3,r2=2sin(θ)

71. r12=sinθ,r22=cosθr12=sinθ,r22=cosθ

72. r1=1+cosθ,r2=1sinθr1=1+cosθ,r2=1sinθ