3 61. 5i   78. false; Changes to make the statement true will vary.  12  28i  15i  35i2 A sample change is: (3 + 7i)(3 7i) = 9 + 49 = 58 E – 12 13i    which is a real number.   12  35  13i  47  79. false; Changes to make the statement true will vary. 13i The voltage of the A sample change is: circuit is (47 + 13i) volts.  7 3i  7 3i  5 3i  44 6i  22  3 i 2  3 3i 5i E  IR    5 3i 5 3i 34   62. 17 6 10i 9i 15i2 6 15        i 5  3i 17 80. true 2  3   6   15  21  i 6 2i 3i 81.       i i i2 i 4 21  The voltage of the circuit is  i   1 i volts. 4  i 63. Sum: 5  5 15 15  i   i 4 4  5  15 i  7 i 5 5   7 7  i  i  10  28 4i   49  i Product: 2 4 5 15   i 5 5 15  i  i 28  4i  25  5i 15  5i 15  15i2 49 1  25 15   50 40  28 4   i 50 50 64. 72. Answers will vary. – 14 2   i 25 25 73. makes sense 82. 74. does not make sense; Explanations will vary. 1 1 i  i Sample explanation: Imaginary numbers are not undefined. 1 2i 1 2i   1 1   i 1 1   2i i A sample change is: All irrational 75. does not make sense; Explanations will vary. numbers are complex numbers. Sample explanation:  1 ; It is not a variable in i  this context. 1 1 1 1 2i 2i 2i     1 1 1 1   2i    i i 76. makes sense 1 1  2i  77. false; Changes to make the statement true will vary.
61. E    5i 3   12  28i  15i  35i2  12  13i   12  35  13i  47  13i The voltage of the circuit is (47 + 13i) volts. 78. false; Changes to make the statement true will vary. A sample change is: (3 + 7i)(3 – 7i) = 9 + 49 = 58 which is a real number. 79. false; Changes to make the statement true will vary. A sample change is: 7 3i  7 3i  5 3i  44 6i  22  3 i 62. E  IR  2  3i  3  5i  6  10i  9i  15i2  6  i  15 5  3i 80. true 5  3i 5  3i 34 17 17  6  i  15  21  i The voltage of the circuit is 21  i  volts. 63. Sum: 5  i 15   5  i 15 4 4 81. 2  i  3  i   6  2i  3i  i2 4  i  1 4  i  5  i 15  5  5  10 Product:  5  i 15  4  7 i 7  i 7  i  28  4i 49  i 2 5  i 15 5  i  25  5i 15  5i 15  15i2  28 4i 49  1  25  15  40 64. – 72. Answers will vary. 73. makes sense 74. does not make sense; Explanations will vary. Sample explanation: Imaginary numbers are not 82. 50 28 4   i 50 50 14 2   i 25 25 1 i  1 i undefined. 1  2i 1  2i 1  i 1  1  i 1  2i 75. does not make sense; Explanations will vary. Sample explanation: i  1 ; It is not a variable in this context. 76. makes sense 77. false; Changes to make the statement true will vary. A sample change is: All irrational numbers are complex numbers.  1  2i 1  2i 1  2i 1  1  i 1  2i  1  i 1  1  2i 1 
Precalculus-Essentials-5th-Edition-Blitzer-Solutions-Manual.docx