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← Make the Denominator Real - College Algebra

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Showing Revision 2 created 05/24/2016 by Udacity Robot.

  1. We've been talking a lot about complex numbers together, but what if we have a
  2. situation like this, where we have one complex number divided by another complex
  3. number? Since right now, both the numerator and the denominator each have a real
  4. and an imaginary component and one is not directly a factor of the other one, we
  5. can't do anything with this expression. We often encounter fractions like this,
  6. and usually, what we do to manipulate them differently is to change the
  7. denominator in some way. What I'd like us to do then is to figure out how to
  8. change the denominator of this fraction so that it ends up being the smallest
  9. real number we can make it, other than 0, of course, since we don't want to
  10. divide by 0. So, think critically about the past few quizzes we've done and what
  11. you can multiply one complex number by to get a real number. Fill in whatever we
  12. need to multiply at the top and bottom of this fraction by, to come up with an
  13. equivalent fraction that has a real number in the denominator. I know this is
  14. new and it probably feels a little bit difficult right now but just give it a
  15. shot, and if you feel like you need to review a little bit to prepare for this
  16. question, you can go back and what the past couple of videos.