Copy of Division of Complex Numbers

Author:
Emily Gorman, Kevin Hopkins
In order to divide complex numbers, we need to know how to multiply them. This is because the most important step in dividing one complex number by another is multiplying both the numerator and the denominator by the conjugate of the denominator. Do you remember what this will do to the denominator? (If not, go back an activity.) Once we've simplified both the numerator and denominator by reducing powers of i and combining like terms, we can cancel any factor common to the numerator and denominator.

Here's an example of a worked division problem:

Here's an example of a worked division problem:
Because 43, 6, and 65 share no common factors, you cannot simplify the answer any further. You could rewrite it as two separate fractions, (43/65)-(6i/65), but that is not necessary.

Now practice on your own.

For video explanation see https://www.khanacademy.org/math/algebra/complex-numbers/complex_numbers/v/dividing-complex-numbers or http://patrickjmt.com/complex-numbers-multiplying-and-dividing/
You should now go to deltamath and complete the practice problems in the section "Divide Complex Numbers".

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