Khan Academy
Introduction to Complex Numbers, Imaginary and Complex Numbers, Precalculus
This video continues looking at dividing complex numbers by looking at the conjugate of a complex number. The instructor then uses the conjugate to rationalize the denominator of a rational expression with a complex number in the...
Flipped Math
Complex Numbers
Simplify the complex with a thorough video lesson. Individuals view a lesson on complex numbers and then use a provided set of practice problems to show what they've learned. The lesson includes instruction on using the four basic...
Welch Labs
Imaginary Numbers Are Real (Part 1: Introduction)
What are imaginary numbers? An introductory video provides an explanation as to why we need imaginary numbers to solve equations, and makes the connection between the need for zero, negative numbers, and rational numbers throughout...
Welch Labs
Imaginary Numbers Are Real (Part 4: Bombelli's Solution)
Is the square root of negative one crucial to the process of finding other solutions? Using the properties of the newly discovered square root of negative one, historical mathematician Bobelli is able to solve Cardan's problem. His...
Welch Labs
Imaginary Numbers Are Real (Part 3: Cardan's Problem)
Were complex numbers discovered or invented? A video presentation makes the case for the discovery of square roots of negative one. In order for complex numbers to be real, then they must behave like other numbers, which they do in terms...
Welch Labs
Imaginary Numbers Are Real (Part 2: A Little History)
In some cases, a square root of a negative number must exist in order to determine the roots of a cubic equation. An educational presentation provides a specific example of a cubic with a known root to have an understanding of a...
Khan Academy
Khan Academy: Algebra: Complex Numbers: Complex Numbers (Part 2)
Video shows how to divide complex numbers by using complex conjugates in general terms and then with a specific example. [8:58]
Khan Academy
Khan Academy: Algebra: Complex Numbers: Complex Numbers (Part 1)
Video first reviews what imaginary and complex numbers are. Shows example of graphing a complex number. Gives general explanations and formulas for adding, subtracting, multiplying and dividing complex numbers. Includes link to...
Khan Academy
Khan Academy: Intro to Complex Number Conjugates
An instructional video describing complex conjugates. Complex conjugates are defined and then used to simplify a problem in which a complex number is divided by another complex number. [8:03]
Khan Academy
Khan Academy: Pre Calculus: Basic Complex Analysis
A video [13:04] introducing complex analysis. Complex numbers are defined as a number having two parts: a real part and an imaginary part. The instructor shows how to graph these in the complex number plane. The video also explains how...
Khan Academy
Khan Academy: Pre Calculus: Exponential Form to Find Complex Roots
This video illustrates how the exponential form of a complex number can be helpful in finding the complex roots of a number. The process is shown both algebraically and graphically using x^3 = 1 as a simple example. [11:53]
Khan Academy
Khan Academy: Algebra: Complex Numbers: Adding Complex Numbers
Video shows an example of adding complex numbers. Includes link to additional practice problems. [1:11]
Khan Academy
Khan Academy: Algebra: Complex Numbers 2
Students learn about complex numbers. The resource examines how to divide complex numbers and complex conjugates. The video tutorial investigates the mathematics concept through detailed notes and examples.
Khan Academy
Khan Academy: Algebra: Complex Numbers 1
Students learn about complex numbers. The resource examines how to add, subtract, and multiply complex numbers. The video tutorial investigates the mathematics concept through detailed notes and examples.
Khan Academy
Khan Academy: Complex Numbers: Complex Numbers (Part 1)
Introduction to complex numbers. Adding, subtracting and multiplying complex numbers.
Khan Academy
Khan Academy: Algebra: Complex Numbers
Video explains what complex numbers are and shows how to write them. Includes an example of writing a real number as a complex number. [2:21]
Khan Academy
Khan Academy: Algebra: Complex Numbers: Imaginary Roots of Negative Numbers
Video shows how to simplify the square root of a negative number using the imaginary unit i. [4:04]
Khan Academy
Khan Academy: The Imaginary Unit I: Imaginary Roots of Negative Numbers
Video shows how to simplify the square root of a negative number using the imaginary unit i.
Khan Academy
Khan Academy: Complex Numbers: Complex Numbers (Part 2)
Dividing complex numbers. Complex conjugates.
University of New South Wales (Australia)
Unsw: How to Solve Polynomial Equations Involving Complex Numbers
The instructor in this video demonstrates how to use the polar form of a complex number to solve a polynomial equation. [11:07]
Khan Academy
Khan Academy: Algebra: Complex Numbers: Introduction to I and Imaginary Numbers
Video introduces i as the imaginary unit, gives two versions of the definition for i, and then shows what various powers of i equal. [5:20]
PatrickJMT
Patrick Jmt: Complex Numbers: Multiplying and Dividing
Video tutorial provides examples of how to multiply and divide complex numbers. [7:22]
PatrickJMT
Patrick Jmt: Complex Numbers: Multiplying Ex 1
Video provides a couple of examples of multiplying two complex numbers and simplifying. [4:51]