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Dividing complex numbers review

Review your complex number division skills.

How do we divide complex numbers?

Dividing a complex number by a real number is simple. For example:
Finding the quotient of two complex numbers is more complex (haha!). For example:
We multiplied both sides by the conjugate of the denominator, which is a number with the same real part and the opposite imaginary part. What's neat about conjugate numbers is that their product is always a real number. Let's continue:
Multiplying the denominator (3+2i) by its conjugate (32i) had the desired effect of getting a real number in the denominator. To keep the quotient the same, we had to multiply the numerator by (32i) as well. Now we can finish the calculation:
Want to learn more about dividing complex numbers? Check out this video.

Check your understanding

Problem 1

Want to try more problems like this? Check out this exercise.