This mini lecture appears in the textbook, Trigonometry, published by XYZ Textbooks. The video appears in the eBook and is also accessible through one of the QR codes in Chapter 5 of the printed book. Access to all the eBooks at XYZ Textbooks is $45 per year. The print book sells for $50 and includes access to all the eBooks for a year. There are over 700 instructional videos embedded into the eBook, and more are added each year.
