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Complex numbers

10 videos
6 skills
Let's start constructing numbers that have both a real and imaginary part. We'll call them complex. We can even plot them on the complex plane and use them to find the roots of ANY quadratic equation. The fun must not stop!

The complex plane

PRACTICE PROBLEMS
Plot complex numbers on the complex plane.

Adding complex numbers

VIDEO 1:11 minutes
Adding Complex Numbers

Subtracting complex numbers

VIDEO 1:53 minutes
Subtracting Complex Numbers

Multiplying complex numbers

VIDEO 5:32 minutes
Multiplying Complex Numbers

Multiplying complex numbers

PRACTICE PROBLEMS

Complex conjugates example

VIDEO 4:01 minutes
Complex Conjugates

Dividing complex numbers

VIDEO 4:58 minutes
Dividing Complex Numbers

Dividing complex numbers

PRACTICE PROBLEMS

Absolute value of complex numbers

PRACTICE PROBLEMS
Find the absolute value of a complex number.

Example: Complex roots for a quadratic

VIDEO 10:15 minutes
Complex Roots from the Quadratic Formula

Algebra II: Imaginary and complex numbers

VIDEO 9:55 minutes
21-26, mostly imaginary and complex numbers