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Unit: Complex numbers

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Possible mastery points

The imaginary unit i

Learn
Intro to the imaginary numbers
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Intro to the imaginary numbers
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Simplifying roots of negative numbers
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Powers of the imaginary unit
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Powers of the imaginary unit
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i as the principal root of -1
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Practice
Simplify roots of negative numbersGet 3 of 4 questions to level up!
Powers of the imaginary unitGet 3 of 4 questions to level up!

Complex numbers introduction

Learn
Intro to complex numbers
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Intro to complex numbers
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Classifying complex numbers
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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

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

Quiz 1

Level up on the above skills and collect up to 500 Mastery points

Adding & subtracting complex numbers

Learn
Adding complex numbers
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Subtracting complex numbers
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Practice
Add & subtract complex numbersGet 3 of 4 questions to level up!

Multiplying complex numbers

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

Quadratic equations with complex solutions

Learn
Solving quadratic equations: complex roots
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Practice
Solve quadratic equations: complex solutionsGet 3 of 4 questions to level up!

Quiz 2

Level up on the above skills and collect up to 400 Mastery points
Up next for you:

Unit test

Level up on all the skills in this unit and collect up to 900 Mastery points!

About this unit

Complex numbers are built on the idea that we can define the number i (called "the imaginary unit") to be the principal square root of -1, or a solution to the equation x²=-1. From this starting point evolves a rich and exciting world of the number system that encapsulates everything we have known before: integers, rational, and real numbers.