 # Complex Numbers

Related Topics:
Common Core (The Complex Number System)
Common Core for Mathematics

Videos and lessons to help High School students know there is a complex number i such that i2 = –1, and every complex number has the form a + bi with a and b real.

### Suggested Learning Targets

• I know what are imaginary numbers and complex numbers.
• I can write complex number in the form a + bi with a and b real.
• I can simplify square roots of negative numbers using i.
• I can rewrite arbitrary powers of i.
Common Core: HSN-CN.A.1

### Imaginary and Complex Numbers

Imaginary Numbers Introduction
i2 = − 1
Solving Equations with i in the solution.
What Are Complex Numbers?
Imaginary Number: Square is a nonpositive real number
Complex Number: Square is a nonnegative real number
0 is both a complex and an imaginary number
Complex number has the form a + bi with a and b real
How to plot complex numbers on the Cartesian plane?

Introduction to i and Imaginary Numbers

### Square Root of Negative Numbers

Simplifying Square Roots of Negative Numbers Using i. Expressing Square Roots of Negative Numbers with i
This video looks at simplifying square roots with negative numbers using the imaginary unit i. It includes 6 examples.

### Rewrite Powers of i

Calculating i Raised to Arbitrary Exponents. Rewriting Powers of ' i ' - Ex 1
Complex number ' i ', raise it to some different powers, and simplify. Rewriting Powers of ' i ' - Ex 2
i raise to a negative power.

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