Basic Mathematics by Serge Lang - 1.5 Rationals (Basic Mathematics)

Let's do what we did for integers but for rationals. Rationals are a ratio of two integers. Unlike integers, you can do some pretty nifty things with rationals, such as cross-multiplication. I've changed the format a bit. Now I'm using an 8.5"x14" paper, so the writing will appear smaller. Let me know if it is too small. I've also tried to improve the lighting and moved my "studio" to a more secure desk so there should be less shaking. I'm going to experiment writing down the important equations on flashcards so I can refer back to them. I'll put proofs and examples on the paper. Some words of encouragement: It's important to keep on trucking, and give your brain time to process what I'm teaching. I'm teaching one part technique and three parts theory, because theory is going to be so critical in physics. Support Real Physics by buying the book through this Amazon affiliate link: https://amzn.to/2I5yIHr Here's my Patreon account if you want to give me money: https://www.patreon.com/realphysics Other ways to support Real Physics: https://youtu.be/44nldGgJCiw Playlist: https://www.youtube.com/playlist?list=PLMcpDl1Pr-viA25VUkHNmcUkWx9usPgyb Thank you!