Back to the Table of Contents

Numbers and Their Application to Math and Science

Odd Solutions for HW Numbers Lesson 15

    Perform the following operations with complex numbers: (Show work!! Only use a calculator to check your answer.) Problems 1-5 and 7-11 are 2 points each, whereas problems 6 and 12 are 5 points each.
  1. (3 + 5i) + (8 + 9i) = 3 + 8 + 5i + 9i = 11 + 14i

  3. (7 + 13i) - (8 + 2i) = 7 - 8 + 13i - 2i = -1 + 11i

  5. (-3i) - (13 + 4i) = 0 - 13 - 3i - 4i = -13 - 7i

  7. (1 + 2i)(1 - 2i) = 1 - 4i2 = 1 + 4 = 5

  9. (3 + 2i)2 = 9 + 12i + 4i2 = 9 - 4 + 12i = 5 + 12i

  11. |(3 + 5i)| = (32 + 52) = (9 + 25) = (34) (Don't include the i!)

  13. Assuming the cube roots of 1 are equally spaced around the unit circle, you know the real one (1), and the two complex ones are complex conjugates of each other; graph them and find approximate values for them.
                                                           
                                                           
                                                           
                                                           
                                                           
                                                           
                                                           
                                                           
                                                           
                                                           
                                                           

BACK to the LESSON HOMEWORK ACTIVITY Table of Contents