1. Complex Numbers: Dividing
and write the result in standard form.
Example: Divide
First, multiply the numerator and denominator by the complex conjugate of the denominator. (Recall the complex conjugate of a + bi is a – bi.)
Here, the complex conjugate of i is 2 – i.

2. Complex Numbers: Dividing
Now, write the result in standard form (a + bi, where a and b are real numbers).
Here
becomes
Try to divide
and write the result in standard form.
The result is,
Slide 2

3. Complex Numbers: Dividing
Notes: If the denominator is a pure imaginary number, say 3i, then it is not necessary to multiply the numerator and denominator by the complex conjugate which would be i here. Instead, it is quicker to multiply the numerator and denominator by just i since this will result in i2 in the denominator, hence the "disappearance” of i from the denominator.
For example,
becomes
Slide 3

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Complex Numbers: Dividing
END OF PRESENTATION
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