Intro to the imaginary numbers (video)

Learn for free about math, art, computer programming, economics, physics, chemistry, biology, medicine, finance, history, and more. Khan Academy is a nonprofit with the mission of providing a free, world-class education for anyone, anywhere.
Learn about the imaginary unit, "i", a unique number defined as the square root of -1. It's a key part of complex numbers, which are in the form a + bi. The powers of "i" cycle through a set of values.

Imaginary Numbers - Calculating

What is the square root of [math]-5^2[/math]? - Quora

What is 5 squared? - Quora

Intro to Complex Numbers / Imaginary Numbers (Notes, WS, Quiz & Answer Keys)

What are the 5th roots of 5-i? - Quora

Video on imaginary numbers and some queries

Intro to Imaginary Numbers: Internet Scavenger Hunt

What is the square root of -9? - Quora

What are some interesting facts about square roots that are not already known? Are there any unsolved problems related to square roots? - Quora