Stein: It used to be, Ms. Dyas taught Analysis 1B with me. But she wouldn't teach the root test. So I made a deal. I'd teach fluid force, and she'd teach the root test. And now she's gone, and I don't teach fluid force.
Rose: Mrs. Dyas would tell you to memorize this. However, all I want you to be able to do is derive this... in seconds.