N-CN.5
Represent addition, subtraction, multiplication, and conjugation of complex numbers geometrically on the complex plane; use properties of this representation for computation. For example, (–1 + √3 i)^3 = 8 because (–1 + √3 i) has modulus 2 and argument 120°.
Example Problems
Consider the complex number:
What is ?
What is ?
Consider the complex number:
What is ?
What is ?
Consider the complex number:
What is ?
What is ?
Khan Academy ResourcesComplex number polar form reviewVisualizing complex number multiplicationVisualizing complex number powersGraphically add & subtract complex numbers Multiply & divide complex numbers in polar formPowers of complex numbersGraphically multiply complex numbersComplex number conjugatesComplex number equations: x³=1Intro to complex number conjugatesDividing complex numbers in polar formTaking and visualizing powers of a complex numberMultiplying complex numbers in polar formMultiplying complex numbers graphically example: -1-iMultiplying complex numbers graphically example: -3i

1-on-1 AI tutoring aligned to N-CN.5. Instant help for students, real-time insights for teachers.
Used in classrooms by 100,000+ students at Baltimore County, Plano ISD, Deer Valley USD, KIPP, and districts nationwide.
Free for teachers, forever →