# Complex Numbers 4

Taught by YourMathGal
• Currently 4.0/5 Stars.
2219 views | 2 ratings
Part of video series
Meets NCTM Standards:
Lesson Summary:

In this lesson on complex numbers, the instructor provides several examples on how to multiply and square complex numbers in standard form, including the importance of understanding imaginary units. The lesson also defines complex conjugates and explains their product. The instructor shows shortcuts for squaring complex numbers and simplifying products of conjugates. By the end of the video, students will have gained a solid understanding of complex number multiplication and how to recognize and work with conjugates.

Lesson Description:

Several examples are provided, showing how to multiply, and square complex numbers in standard form. Also, complex conjugates are defined and the product of complex conjugates is shown.

More free YouTube videos by Julie Harland are organized at http://yourmathgal.com

• How do you square complex numbers?
• How do you multiply two complex numbers with both real and imaginary parts?
• What is (2 + 3i)^2?
• What is (4 + 3i)(4 - 3i)?
• How do you multiply (6 - 5i)(6 + 5i)?
• What does (3 + 5i)(3 - 5i) equal?
• How do you multiply (7 + i)(7 - i)?
• How do you square (7 + i)?
• What are complex conjugates?
• What happens when you multiply two complex conjugates?
• #### Staff Review

• Currently 4.0/5 Stars.
This lesson has a lot of practice problems showing how to multiply complex numbers that have both a real and imaginary part to them, so they look and act just like binomial expressions, but i^2 = -1. Many different example problems are shown and solved in this lesson. FOIL is shown and explained for squaring complex numbers, multiplying complex numbers, and multiplying complex conjugates.