+
Lesson Plan
Curated OER

Complex Numbers

For Teachers 10th - 12th
In this complex numbers worksheet, students write numbers as a multiple of i. They add and subtract imaginary numbers. Students write complex quotients in standard form. This three-page worksheet contains six problems.
+
Lesson Plan
Curated OER

Complex Numbers - Week 5

For Teachers 10th - 11th
In this complex numbers worksheet, students solve problems involving polynomials, real constants containing imaginary numbers, and find the complex number that satisfies a given equation. This two-page worksheet contains seven problems.
+
Worksheet
Math About

Introduction to Complex Numbers

For Students 10th - 12th Standards
In this complex number learning exercise, students explore the properties of imaginary numbers to find the square roots of negative numbers. Explanations and examples are given prior to the exercise. This two-page learning exercise...
+
Handout
Clark University

Clark University: Dave's Short Trig Course: Complex Numbers: Absolute Value

For Students 9th - 10th Standards
Contains detailed information on absolute values for complex numbers.
+
Handout
Cut the Knot

Cut the Knot!: What Is a Number?

For Students 9th - 10th Standards
Casual and clear but definitely upper-level discussion of rational, real, imaginary, and several other types of numbers. Links to related sites.
+
Handout
Math Is Fun

Math Is Fun: The Evolution of Numbers

For Students 9th - 10th Standards
Discusses what numbers are and how our understanding of them has evolved over thousands of years, from simple counting to negative numbers and irrational numbers, for example. Includes a set of practice questions where students identify...
+
Activity
Oswego City School District

Regents Exam Prep Center: Cyclic Nature of the Powers of "I"

For Students 9th - 10th
Students learn two easy methods to simplify "i" with any exponent. The practice page has several problems that include explanations. The teacher resource page has two possible activities for helping students understand the concept.
+
Handout
Wolfram Research

Wolfram Math World: I

For Students 9th - 10th
The imaginary number (also called the imaginary unit) is defined as the square root of negative one. This site explains the rational for the existence of the imaginary number "i" and gives formulas involving "i" including Euler's...
+
Activity
Oswego City School District

Regents Exam Prep Center: Simplifying Square Roots With Negative Numbers

For Students 9th - 10th
This tutorial and practice shows how to simplify radicals even with a negative number. Features include a teacher page that has a Bingo game to teach the concept.
+
Activity
Oswego City School District

Regents Exam Prep Center: Absolute Value of Complex Numbers

For Students 9th - 10th Standards
This tutorial presents the absolute value of complex numbers using formulas, graphs, and examples. There are practice problems and a teacher resource page to assist students in understanding the concept.
+
Unit Plan
Cuemath

Cuemath: Complex Numbers

For Students 9th - 10th Standards
A comprehensive guide for learning all about complex numbers with definitions, operations on complex numbers, solved examples, and practice questions.
+
Handout
Wolfram Research

Wolfram Math World: Imaginary Number

For Students 9th - 10th Standards
Contains a brief definition of an imaginary number. Includes special links and topic search engine.
+
Activity
Math Medics

S.o.s. Math: The Complex Numbers

For Students 9th - 10th Standards
This lesson may be useful to both persons with prior knowledge of complex numbers and those without. The lesson begins with the definition of complex numbers and its notation, then gives the rules of arithmetic for them with exercises....
+
Graphic
Clark University

Clark University: Dave's Short Trig Course: Complex Numbers

For Students 9th - 10th Standards
This site from a professor at Clark University teaches you about complex numbers.
+
Handout
University College London

University College London: Complex Numbers: Real and Imaginary Parts

For Students 9th - 10th Standards
Contains a brief summary about the real and imaginary parts of complex numbers.
+
Unit Plan
CK-12 Foundation

Ck 12: Analysis: Imaginary Numbers

For Students 10th - 12th Standards
[Free Registration/Login may be required to access all resource tools.] In this lesson students will identify imaginary and complex numbers, basic evaluation of imaginary numbers. Students examine guided notes, review guided practice,...
+
Unit Plan
CK-12 Foundation

Ck 12: Analysis: Products and Quotients of Complex Numbers

For Students 10th - 12th Standards
[Free Registration/Login may be required to access all resource tools.] This lesson covers multiplying and dividing complex numbers. Students examine guided notes, review guided practice, watch instructional videos and attempt practice...
+
Unit Plan
Khan Academy

Khan Academy: Powers of the Imaginary Unit

For Students 9th - 10th Standards
Simplify expressions with base i (the imaginary unit) raised to a positive exponent. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
+
Unit Plan
Khan Academy

Khan Academy: Simplify Roots of Negative Numbers

For Students 9th - 10th Standards
Rewrite square roots of negative numbers as imaginary numbers. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
+
Handout
Other

Mrao: Imaginary Numbers Are Not Real

For Students 9th - 10th Standards
This site presents a tutorial introduction to the ideas of geometric algebra. Gives an outline of geometric algebra and discusses the geometric product, imaginary numbers, and more.
+
eBook
Math Planet

Math Planet: Algebra 2: Complex Numbers

For Students 9th - 10th Standards
Provides an explanation, examples, and a video lesson all related to complex numbers.
+
Handout
Math Warehouse

Math Warehouse: Complex and Imaginary Numbers

For Students 9th - 10th Standards
Features numerous exercises relating to complex and imaginary numbers. Includes video tutorials, calculators, worksheets and more.
+
Handout
Math Open Reference

Math Open Reference: Number

For Students 9th - 10th
Resource defines numbers into two main categories, counting numbers and scalars. It also gives examples of number notation.
+
Handout
Math Open Reference

Math Open Reference: Root (Of a Number)

For Students 9th - 10th Standards
Learn how to find the root of a number. Topics covered include two roots, roots of negative numbers, and imaginary numbers. This site offers descriptions along with multiple examples.