Ch 9: Complex and Imaginary Numbers: Help and Review

About This Chapter

The Complex and Imaginary Numbers chapter of this College Preparatory Mathematics Help and Review course is the simplest way to master complex and imaginary numbers. This chapter uses simple and fun videos that are about five minutes long, plus lesson quizzes and a chapter exam to ensure students learn the essentials of complex and imaginary numbers.

Who's it for?

Anyone who needs help learning or mastering college preparatory math material will benefit from taking this course. You will be able to grasp the subject matter faster, retain critical knowledge longer and earn better grades. You're in the right place if you:

  • Have fallen behind in understanding imaginary numbers or how to work with complex numbers.
  • Need an efficient way to learn about complex and imaginary numbers.
  • Learn best with engaging auditory and visual tools.
  • Struggle with learning disabilities or learning differences, including autism and ADHD.
  • Experience difficulty understanding your teachers.
  • Missed class time and need to catch up.
  • Can't access extra math learning resources at school.

How it works:

  • Start at the beginning, or identify the topics that you need help with.
  • Watch and learn from fun videos, reviewing as needed.
  • Refer to the video transcripts to reinforce your learning.
  • Test your understanding of each lesson with short quizzes.
  • Submit questions to one of our instructors for personalized support if you need extra help.
  • Verify you're ready by completing the Complex and Imaginary Numbers chapter exam.

Why it works:

  • Study Efficiently: Skip what you know, review what you don't.
  • Retain What You Learn: Engaging animations and real-life examples make topics easy to grasp.
  • Be Ready on Test Day: Use the Complex and Imaginary Numbers chapter exam to be prepared.
  • Get Extra Support: Ask our subject-matter experts any relevant question. They're here to help!
  • Study With Flexibility: Watch videos on any web-ready device.

Students will review:

In this chapter, you'll learn the answers to questions including:

  • What is an imaginary number?
  • How do I add, subtract, multiply and divide complex numbers?
  • What steps and terms do I need to know to graph a complex number?
  • How do I use imaginary numbers to solve quadratic equations?

5 Lessons in Chapter 9: Complex and Imaginary Numbers: Help and Review
Test your knowledge with a 30-question chapter practice test
What is an Imaginary Number?

1. What is an Imaginary Number?

The imaginary number 'i' is the square root of -1. Although this number doesn't actually exist, pretending that it does allows us to do a bunch of crazy math that scientists use every day. Learn the basics of that number 'i' here!

How to Add, Subtract and Multiply Complex Numbers

2. How to Add, Subtract and Multiply Complex Numbers

Knowing that complex numbers exist is the first step. But that knowledge alone won't help you do much with them. Learn the basics of complex number addition, subtraction and multiplication here!

How to Divide Complex Numbers

3. How to Divide Complex Numbers

While adding, subtracting and multiplying complex numbers is pretty straightforward, dividing them can be pretty tricky. It comes down to the process of multiplying by the complex conjugate. Learn about what that is, and how to do it, here.

How to Graph a Complex Number on the Complex Plane

4. How to Graph a Complex Number on the Complex Plane

Graphing complex numbers is pretty straight forward, but it's not necessarily intuitive. Check out this lesson to learn the vocabulary and the conventions that you'll need.

How to Solve Quadratics with Complex Numbers as the Solution

5. How to Solve Quadratics with Complex Numbers as the Solution

When you solve a quadratic equation with the quadratic formula and get a negative on the inside of the square root, what do you do? The short answer is that you use an imaginary number. For the longer, more helpful answer, check out this lesson!

Chapter Practice Exam
Test your knowledge of this chapter with a 30 question practice chapter exam.
Not Taken
Practice Final Exam
Test your knowledge of the entire course with a 50 question practice final exam.
Not Taken

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