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Unit: Complex numbers

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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!
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
(Opens a modal)

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Distance of complex numbersGet 3 of 4 questions to level up!
Midpoint of complex numbersGet 3 of 4 questions to level up!

Quiz 1

Level up on the above skills and collect up to 320 Mastery points

Complex conjugates and dividing complex numbers

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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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Practice

Factor polynomials: complex numbersGet 3 of 4 questions to level up!

Quiz 2

Level up on the above skills and collect up to 240 Mastery points

Modulus (absolute value) and argument (angle) of complex numbers

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Practice

Modulus (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!

Quiz 3

Level up on the above skills and collect up to 240 Mastery points

Polar form of complex numbers

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Practice

Complex plane and polar formGet 3 of 4 questions to level up!
Polar & rectangular forms of complex numbersGet 3 of 4 questions to level up!

Graphically multiplying complex numbers

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Practice

Graphically multiply complex numbersGet 3 of 4 questions to level up!

Multiplying and dividing complex numbers in polar form

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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!

Quiz 4

Level up on the above skills and collect up to 400 Mastery points

The fundamental theorem of algebra

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Up next for you:

Unit test

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About this unit

In Algebra 2, students were introduced to the complex numbers and performed basic operations with them. In this unit, we extend this concept and perform more sophisticated operations, like dividing complex numbers. We also learn about a different way to represent complex numbers—polar form.