Problem Set 6: Absolute Value Functions

1. How do you solve an absolute value equation?

2. How can you tell whether an absolute value function has two x-intercepts without graphing the function?

3. When solving an absolute value function, the isolated absolute value term is equal to a negative number. What does that tell you about the graph of the absolute value function?

4. How can you use the graph of an absolute value function to determine the x-values for which the function values are negative?

5. How do you solve an absolute value inequality algebraically?

6. Describe all numbers x that are at a distance of 4 from the number 8. Express this using absolute value notation.

7. Describe all numbers x that are at a distance of 12 from the number −4. Express this using absolute value notation.

8. Describe the situation in which the distance that point x is from 10 is at least 15 units. Express this using absolute value notation.

9. Find all function values f(x) such that the distance from f(x) to the value 8 is less than 0.03 units. Express this using absolute value notation.

For the following exercises, solve the equations below and express the answer using set notation.

10. |x+3|=9

11. |6x|=5

12. |5x2|=11

13. |4x2|=11

14. 2|4x|=7

15. 3|5x|=5

16. 3|x+1|4=5

17. 5|x4|7=2

18. 0=|x3|+2

19. 2|x3|+1=2

20. |3x2|=7

21. |3x2|=7

22. |12x5|=11

23. |13x+5|=14

24. |13x+5|+14=0

For the following exercises, find the x- and y-intercepts of the graphs of each function.

25. f(x)=2|x+1|10

26. f(x)=4|x3|+4

27. f(x)=3|x2|1

28. f(x)=2|x+1|+6

For the following exercises, solve each inequality and write the solution in interval notation.

29. |x2|>10

30. 2|v7|442

31. |3x4|8

32. |x4|8

33. |3x5|13

34. |3x5|13

35. |34x5|7

36. |34x5|+116

For the following exercises, graph the absolute value function. Plot at least five points by hand for each graph.

37. y=|x1|

38. y=|x+1|

39. y=|x|+1

For the following exercises, graph the given functions by hand.

40. y=|x|2

41. y=|x|

42. y=|x|2

43. y=|x3|2

44. f(x)=|x1|2

45. f(x)=|x+3|+4

46. f(x)=2|x+3|+1

47. f(x)=3|x2|+3

48. f(x)=|2x4|3

49. f(x)=|3x+9|+2

50. f(x)=|x1|3

51. f(x)=|x+4|3

52. f(x)=12|x+4|3

53. Use a graphing utility to graph f(x)=10|x2| on the viewing window [0,4]. Identify the corresponding range. Show the graph.

54. Use a graphing utility to graph f(x)=100|x|+100 on the viewing window [5,5]. Identify the corresponding range. Show the graph.

For the following exercises, graph each function using a graphing utility. Specify the viewing window.

55. f(x)=(0.1)|0.1(0.2x)|+0.3

56. f(x)=4×109|x(5×109)|+2×109

For the following exercises, solve the inequality.

57. |2x23(x+1)|+3>1

58. If possible, find all values of a such that there are no x- intercepts for f(x)=2|x+1|+a.

59. If possible, find all values of a such that there are no y -intercepts for f(x)=2|x+1|+a.

60. Cities A and B are on the same east-west line. Assume that city A is located at the origin. If the distance from city A to city B is at least 100 miles and x represents the distance from city B to city A, express this using absolute value notation.

61. The true proportion p of people who give a favorable rating to Congress is 8% with a margin of error of 1.5%. Describe this statement using an absolute value equation.

62. Students who score within 18 points of the number 82 will pass a particular test. Write this statement using absolute value notation and use the variable x for the score.

63. A machinist must produce a bearing that is within 0.01 inches of the correct diameter of 5.0 inches. Using x as the diameter of the bearing, write this statement using absolute value notation.

64. The tolerance for a ball bearing is 0.01. If the true diameter of the bearing is to be 2.0 inches and the measured value of the diameter is x inches, express the tolerance using absolute value notation.