Complex Numbers 6

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Taught by YourMathGal
  • Currently 4.0/5 Stars.
1898 views | 2 ratings
Part of video series
Meets NCTM Standards:
Lesson Summary:

In this lesson on complex numbers, the focus is on how to divide by them. By multiplying the numerator and denominator by the conjugate of the complex number in the denominator, we can simplify and put the answer in the form a plus bi. Through several examples and a careful walkthrough, this comprehensive lesson will ensure that learners are confident in their ability to deal with algebraic type fractions involving complex numbers.

Lesson Description:

Several examples are provided, showing how to divide by complex numbers in standard form by multiplying numerator and denominator by the conjugate of the complex number in the denominator.

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Questions answered by this video:
  • How do you divide complex numbers?
  • How do you get rid of imaginary numbers from the denominators of fractions?
  • How can you use the complex conjugate to simplify a complex fraction?
  • How can you divide 3/(5 - 2i)?
  • How can you simplify 5/(3 + i)?
  • How can you get rid of the imaginary part from the denominator of 10/(3 - 4i)?
  • How do you simplify 4i/(5 + i)?
  • How can you simplify (3 + 2i)/(7 + 2i)?
  • Staff Review

    • Currently 4.0/5 Stars.
    This lesson explains one of the more complicated parts of operations with fractions -- dividing complex numbers in which there is an imaginary part in the denominator. To simplify the fraction by removing the imaginary part, you must multiply the numerator and denominator by the complex conjugate of the denominator. This is a great tutorial on what can be a complicated lesson.