Grade school math students are likely familiar with teachers admonishing them not to just guess the answer to a problem. But a new proof establishes that, in fact, the right kind of guessing is ...

Physics and Python stuff. Most of the videos here are either adapted from class lectures or solving physics problems. I really like to use numerical calculations without all the fancy programming ...

Simultaneous equations Simultaneous examples with no common coefficients Creating and solving simultaneous equations Simultaneous equations with linear and quadratic Solving simultaneous equations ...