# Complex numbers

## What are the imaginary numbers?

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Intro to the imaginary numbersIntro to the imaginary numbersPowers of the imaginary unitPowers of the imaginary unitSimplifying roots of negative numbersi as the principal root of -1
Practice
Powers of the imaginary unitGet 3 of 4 questions to level up!
Simplify roots of negative numbersGet 3 of 4 questions to level up!

## What are the complex numbers?

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Intro to complex numbersIntro to complex numbersClassifying complex numbers
Practice
Parts of complex numbersGet 3 of 4 questions to level up!
Classify complex numbersGet 3 of 4 questions to level up!

## The complex plane

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Plotting numbers on the complex planeThe complex plane
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Plot numbers on the complex planeGet 3 of 4 questions to level up!

## Adding and subtracting complex numbers

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Practice
Add & subtract complex numbersGet 3 of 4 questions to level up!
Graphically add & subtract complex numbers Get 3 of 4 questions to level up!

## Distance and midpoint of complex numbers

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Distance & midpoint of complex numbers
Practice
Distance of complex numbersGet 3 of 4 questions to level up!
Midpoint of complex numbersGet 3 of 4 questions to level up!

## Multiplying complex numbers

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Multiplying complex numbersMultiplying complex numbersComplex number operations review
Practice
Multiply complex numbers (basic)Get 3 of 4 questions to level up!
Multiply complex numbersGet 3 of 4 questions to level up!

## Complex conjugates and dividing complex numbers

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Intro to complex number conjugatesComplex number conjugatesDividing complex numbersDividing complex numbers review
Practice
Complex number conjugatesGet 3 of 4 questions to level up!
Divide complex numbersGet 3 of 4 questions to level up!

## Identities with complex numbers

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Complex numbers & sum of squares factorizationFactoring sum of squares
Practice
Factor polynomials: complex numbersGet 3 of 4 questions to level up!

## Absolute value and angle of complex numbers

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Absolute value of complex numbersAbsolute value & angle of complex numbersComplex number absolute value & angle review
Practice
Absolute value of complex numbersGet 3 of 4 questions to level up!
Angle of complex numbersGet 3 of 4 questions to level up!
Complex numbers from absolute value & angleGet 3 of 4 questions to level up!

## Polar form of complex numbers

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Polar & rectangular forms of complex numbersComplex number forms review
Practice
Polar & rectangular forms of complex numbersGet 3 of 4 questions to level up!

## Multiplying and dividing complex numbers in polar form

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Dividing complex numbers: polar & exponential formVisualizing complex number multiplicationPowers of complex numbersComplex number equations: x³=1Visualizing complex number powersComplex number polar form review
Practice
Multiply & divide complex numbers in polar formGet 3 of 4 questions to level up!
Powers of complex numbersGet 3 of 4 questions to level up!