Khan Academy on a Stick
Imaginary and complex numbers
Understanding and solving equations with imaginary numbers.
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Introduction to i and imaginary numbers
Introduction to i and imaginary numbers
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Calculating i raised to arbitrary exponents
Calculating i raised to arbitrarily high exponents
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Imaginary roots of negative numbers
Imaginary Roots of Negative Numbers
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i as the principal root of -1 (a little technical)
i as the principal square root of -1
The imaginary unit i
This is where math starts to get really cool. It may see strange to define a number whose square is negative one. Why do we do this? Because it fits a nice niche in the math ecosystem and can be used to solve problems in engineering and science (not to mention some of the coolest fractals are based on imaginary and complex numbers). The more you think about it, you might realize that all numbers, not just i, are very abstract.
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Introduction to complex numbers
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Plotting complex numbers on the complex plane
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Adding complex numbers
Adding Complex Numbers
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Subtracting complex numbers
Subtracting Complex Numbers
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Multiplying complex numbers
Multiplying Complex Numbers
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Complex conjugates example
Complex Conjugates
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Dividing complex numbers
Dividing Complex Numbers
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Absolute value of a complex number
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Example: Complex roots for a quadratic
Complex Roots from the Quadratic Formula
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Algebra II: Imaginary and complex numbers
21-26, mostly imaginary and complex numbers
Complex numbers
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!