Solutions to Try Its
1. a. yes; b. yes. (Note: If two players had been tied for, say, 4th place, then the name would not have been a function of rank.)
2. [latex]g\left(5\right)=1[/latex]
3. [latex]m=8[/latex]
4. [latex]y=f\left(x\right)=\frac{\sqrt[3]{x}}{2}[/latex]
5. [latex]g\left(1\right)=8[/latex]
6. [latex]x=0[/latex] or [latex]x=2[/latex]
7. a. yes, because each bank account has a single balance at any given time; b. no, because several bank account numbers may have the same balance; c. no, because the same output may correspond to more than one input.
8. yes
Solutions to Odd-Numbered Exercises
1. A relation is a set of ordered pairs. A function is a special kind of relation in which no two ordered pairs have the same first coordinate.
3. When a vertical line intersects the graph of a relation more than once, that indicates that for that input there is more than one output. At any particular input value, there can be only one output if the relation is to be a function.
5. When a horizontal line intersects the graph of a function more than once, that indicates that for that output there is more than one input. A function is one-to-one if each output corresponds to only one input.
7. function
9. function
11. function
13. function
15. function
17. function
19. function
21. function
23. function
25. not a function
27. [latex]f\left(-3\right)=-11\\ f\left(2\right)=-1\\ f\left(-a\right)=-2a - 5\\-f\left(a\right)=-2a+5\\f\left(a+h\right)=2a+2h - 5[/latex]
29. [latex]f\left(-3\right)=\sqrt{5}+5\\ f\left(2\right)=5\\ f\left(-a\right)=\sqrt{2+a}+5\\ -f\left(a\right)=-\sqrt{2-a}-5\\f\left(a+h\right)=\\sqrt{2-a-h}+5[/latex]
31. [latex]f\left(-3\right)=2\\f\left(2\right)=1 - 3=-2\\f\left(-a\right)=|-a - 1|-|-a+1|\\ -f\left(a\right)=-|a - 1|+|a+1|\\\text{ }\text{ }f\left(a+h\right)=|a+h - 1|-|a+h+1|[/latex]
33. [latex]\frac{g\left(x\right)-g\left(a\right)}{x-a}=x+a+2,x\ne a[/latex]
35. a. [latex]f\left(-2\right)=14[/latex]; b. [latex]x=3[/latex]
37. a. [latex]f\left(5\right)=10[/latex]; b. [latex]x=-1\text{ }[/latex] or [latex]\text{ }x=4[/latex]
39. a. [latex]f\left(t\right)=6-\frac{2}{3}t[/latex]; b. [latex]f\left(-3\right)=8[/latex]; c. [latex]t=6[/latex]
41. not a function
43. function
45. function
47. function
49. function
51. function
53. a. [latex]f\left(0\right)=1[/latex]; b. [latex]f\left(x\right)=-3,x=-2\text{ }[/latex] or [latex]\text{ }x=2[/latex]
55. not a function so it is also not a one-to-one function
57. one-to-one function
59. function, but not one-to-one
61. function
63. function
65. not a function
67. [latex]f\left(x\right)=1,x=2[/latex]
69. [latex]f\left(-2\right)=14\\ f\left(-1\right)=11\\ f\left(0\right)=8\\f\left(1\right)=5\\ f\left(2\right)=2[/latex]
71. [latex]f\left(-2\right)=4\\\text{ }\\ f\left(-1\right)=4.414\\ f\left(0\right)=4.732\\ f\left(1\right)=4.5\\ f\left(2\right)=5.236[/latex]
73. [latex]f\left(-2\right)=\frac{1}{9}\\ f\left(-1\right)=\frac{1}{3}\\ f\left(0\right)=1\\ f\left(1\right)=3;\\f\left(2\right)=9[/latex]
75. 20
77. [latex]\left[0,\text{ 100}\right][/latex]
79.[latex]\left[-0.001,\text{ 0}\text{.001}\right][/latex]
81. [latex]\left[-1,000,000,\text{ 1,000,000}\right][/latex]
83. [latex]\left[0,\text{ 10}\right][/latex]
85. [latex]\left[-0.1,\text{0.1}\right][/latex]
87. [latex]\left[-100,\text{ 100}\right][/latex]
89. a. [latex]g\left(5000\right)=50[/latex]; b. The number of cubic yards of dirt required for a garden of 100 square feet is 1.
91. a. The height of a rocket above ground after 1 second is 200 ft. b. the height of a rocket above ground after 2 seconds is 350 ft.