CK-12 Foundation
Ck 12: Algebra: Use Square Roots to Solve Quadratic Equations
[Free Registration/Login may be required to access all resource tools.] Use square roots to solve quadratic equations.
Integrated Publishing
Integrated Publishing: Irrational Roots
A brief lesson on when irrational roots occur when solving quadratic equations, and how to find them. Contains examples, exercises, and solutions.
Interactive Mathematics
Interactive Mathematics: Complex Numbers: Basic Definitions
After reviewing the process of solving quadratic and cubic equations, a definition of an imaginary number is given. Also included is a demonstration of simplifying powers of the imaginary number and writing complex numbers. Examples are...
Alabama Learning Exchange
Alex: Classifying Complex Numbers
This lesson helps students distinguish between strictly complex numbers, strictly real numbers and strictly imaginary numbers while learning that real numbers and imaginary numbers are subsets of the set of complex numbers.
Math Open Reference
Math Open Reference: Complex Numbers
Explore complex numbers with this easy reference guide. Learn that complex numbers lie on a two-dimensional flat plane and have two components called the real and imaginary parts. Provides definitions and interactive activities that...
Khan Academy
Khan Academy: Simplify Roots of Negative Numbers
Rewrite square roots of negative numbers as imaginary numbers.
Khan Academy
Khan Academy: Solve Quadratic Equations: Complex Solutions
Solve quadratic equations using the quadratic formula. Some of the equations have real solutions while others have complex solutions.
Khan Academy
Khan Academy: Parts of Complex Numbers
Determine the real and the imaginary parts of complex numbers.
Khan Academy
Khan Academy: Multiply Complex Numbers (Basic)
Multiply complex numbers by single terms that are either real or pure imaginary.
Khan Academy
Khan Academy: Add & Subtract Complex Numbers
Practice addition and subtraction with complex numbers.
Cuemath
Cuemath: Imaginary Numbers
In this lesson, you will learn about complex numbers and imaginary numbers. Included are solved examples and interactive questions for review.
CK-12 Foundation
Ck 12: 1.5 From Quadratics to Complex Numbers
This section introduces imaginary and complex numbers in the context of solutions to quadratic equations that don't have real-number solutions.
Math Notes and Math Tests
Pre Calculus Notes: Complex Numbers [Pdf]
The resource discusses complex numbers. Topics examined are the complex plane, complex conjugates, dividing complex numbers, and complex zeros of functions.
Windstream
Ojk's Precalculus Study Page: Solving Polynomial Equations
A comprehensive look at the three main ways to find the roots of a polynomial: factoring, formulas, and the rational root theorem.
Math Words
Math words.com: Complex Numbers
At MathWords.com, a definition is given for what complex numbers are, along with some examples.
Free Math Help
Free Math Help: Imaginary Numbers
The lesson investigates imaginary numbers. An explanation and sample exercises are provided.
Varsity Tutors
Varsity Tutors: Hotmath: Algebra Review: Complex Numbers
Find a quick, concise explanation of Complex Numbers.
Varsity Tutors
Varsity Tutors: Hotmath: Algebra Review: Solving Quadratic Equations With Square Roots
Find a quick, concise explanation for how to solve quadratic equations using square roots. An example is given and clearly explained.
Other
Gobierno De Navarra: Numeros Complejos
Use these interactive activities as a supplementary material to practice sum, difference, multiplication and division, power and roots of complex numbers.
Interactive Mathematics
Interactive Mathematics: De Moivre's Theorem
Using DeMoivre's Theorem, the powers and roots of complex numbers are simplified. Several examples are given, including interactive exercises.
Math Open Reference
Math Open Reference: Imaginary Number
Learn about imaginary numbers with this handy reference guide. Provides a detailed definition and examples that enhance further explanation. Includes links to related topics.
National Council of Teachers of Mathematics
The Math Forum: Restrictions on Roots
A question is asked if there are any restrictions on "n" when talking about the nth root of a number.