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Complex Numbers
Common Core: N.CN.1

Complex Numbers

Author: Graham Pardun

This lesson introduces and explains complex numbers, the imaginary number i, and shows how to do basic add, subtract, and multiply with them.

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What i Means, Where the Number i Came From, What Complex Numbers Are, and How to Add, Subtract, and Multiply Them

What's the square root of -25? Here's an intro to the concept of i, an imaginary number, how i relates to "complex" numbers, and how to handle these complex numbers in ordinary mathematical life!