Solutions

Solutions to Try Its

1. The path passes through the origin and has vertex at (4, 7), so (h)x=716(x+4)2+7. To make the shot, h(7.5) would need to be about 4 but h(7.5)1.64; he doesn’t make it.

2. g(x)=x26x+13 in general form; g(x)=(x3)2+4 in standard form

3. The domain is all real numbers. The range is f(x)811, or [811,).

4. y-intercept at (0, 13), No x-intercepts

5. a. 3 seconds  b. 256 feet  c. 7 seconds

Solutions to Odd-Numbered Exercises

1. When written in that form, the vertex can be easily identified.

3. If a=0 then the function becomes a linear function.

5. If possible, we can use factoring. Otherwise, we can use the quadratic formula.

7. f(x)=(x+1)22, Vertex (1,4)

9. f(x)=(x+52)2334, Vertex (52,334)

11. f(x)=3(x1)212, Vertex (1,12)

13. f(x)=3(x56)23712, Vertex (56,3712)

15. Minimum is 172 and occurs at 52. Axis of symmetry is x=52.

17. Minimum is 1716 and occurs at 18. Axis of symmetry is x=18.

19. Minimum is 72 and occurs at –3. Axis of symmetry is x=3.

21. Domain is (,). Range is [2,).

23. Domain is (,). Range is [5,).

25. Domain is (,). Range is [12,).

27. {2i2,2i2}

29. {3i3,3i3}

31. {2+i,2i}

33. {2+3i,23i}

35. {5+i,5i}

37. {2+26,226}

39. {12+32i,1232i}

41. {35+15i,3515i}

43. {12+12i7,1212i7}

45. f(x)=x24x+4

47. f(x)=x2+1

49. f(x)=649x2+6049x+29749

51. f(x)=x2+1

53. Vertex (1, 1), Axis of symmetry is x=1. Intercepts are (0,0),(2,0).

Graph of f(x) = x^2-2x

55. Vertex (52,494), Axis of symmetry is (0,6),(1,0),(6,0).

Graph of f(x)x^2-5x-6

57. Vertex (54,398), Axis of symmetry is x=54. Intercepts are (0,8).

Graph of f(x)=-2x^2+5x-8

59. f(x)=x24x+1

61. f(x)=2x2+8x1

63. f(x)=12x23x+72

65. f(x)=x2+1

67. f(x)=2x2

69. f(x)=2x2

71. The graph is shifted up or down (a vertical shift).

73. 50 feet

75. Domain is (,). Range is [2,).

77. Domain is (,) Range is (,11].

79. f(x)=2x21

81. f(x)=3x29

83. f(x)=5x277

85. 50 feet by 50 feet. Maximize f(x)=x2+100x.

87. 125 feet by 62.5 feet. Maximize f(x)=2x2+250x.

89. 6 and –6; product is –36; maximize f(x)=x2+12x.

91. 2909.56 meters

93. $10.70