@divinedolphin I'm sorry, you are right, Prof. Loh doesn't mention Viete's Formulas in our course, but he does mention it in this explanation video:

https://www.youtube.com/watch?v=XKBX0r3J-9Y
 

 
I think I got a little confused about where Prof. Loh mentioned it originally.

The spelling of his name varies; sometimes it's spelled as "Vieta," and sometimes it's spelled as "Viete," as shown in Prof. Loh's video.