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.
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.
Unit Plan
Texas A&M University

Wtamu Virtual Math Lab: College Algebra: Complex Numbers

For Students 9th - 10th Standards
Use this tutorial to learn what imaginary and complex numbers are, how to write them, and how to perform operations with them. Offers step-by-step examples, video explanations of the examples, and practice questions with answers.
Handout
Lawrence Hall of Science

The Math Page: Skill in Algebra: Skill in Algebra: Complex or Imaginary Numbers

For Students 9th - 10th Standards
Clearly and thoroughly explains complex numbers. Provides example problems and exercises for students, with solutions available.
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,...
Lesson Plan
Alabama Learning Exchange

Alex: Imaginary Numbers? What Do You Mean Imaginary?

For Teachers 9th - 10th
Is it any wonder that students are suspicious? We lead, sometimes drag, them through Algebra I insisting they must follow the order of operations. We make them learn the "hard way" of doing an assignment one day only to show them the...
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
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...
Unit Plan
CK-12 Foundation

Ck 12: Find Imaginary Solutions: Fundamental Theorem of Algebra

For Students 11th - 12th Standards
[Free Registration/Login may be required to access all resource tools.] Here you will learn about the Fundamental Theorem of Algebra, and how to apply it to various functions. You will also review using the quadratic equation to find...
Unit Plan
CK-12 Foundation

Ck 12: Find Imaginary Solutions

For Students 10th - 12th Standards
[Free Registration/Login may be required to access all resource tools.] In this lesson, students are finding complex roots of polynomials and applications of the Fundamental Theorem of Algebra. Students examine guided notes, review...
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.
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.
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....
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.
Lesson Plan
Alabama Learning Exchange

Alex: Classifying Complex Numbers

For Teachers 9th - 10th Standards
This lesson plan helps learners 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.
eBook
CK-12 Foundation

Ck 12: 1.5 From Quadratics to Complex Numbers

For Students 9th - 10th Standards
This section introduces imaginary and complex numbers in the context of solutions to quadratic equations that don't have real-number solutions.
eBook
CK-12 Foundation

Ck 12: Algebra Ii: 1.6 the Complex Plane

For Students 9th - 10th Standards
This section includes operations with imaginary and complex numbers and plotting numbers on the complex plane.
Unit Plan
CK-12 Foundation

Ck 12: Analysis: Increasing and Decreasing Functions

For Students 9th - 10th
[Free Registration/Login may be required to access all resource tools.] Identification of increasing and decreasing intervals of discrete and non-discrete functions. Students examine guided notes, review guided practice, watch...