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Unit: Complex numbers

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Possible mastery points

The imaginary unit i

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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

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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

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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

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Practice

Add & subtract complex numbersGet 3 of 4 questions to level up!

Multiplying complex numbers

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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

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Solving quadratic equations: complex roots
(Opens a modal)

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.