Non-linear physics is the study of systems where the output is not directly proportional to the input. Unlike linear systems, which follow simple, predictable relationships, non-linear systems exhibit ...

I've been grading calculus exams this week, and even though my students did quite well overall there were a couple of errors that I see every semester. Errors that make mathematicians' heads explode.

This section illustrates how to solve some ordinary least-squares problems and generalizations of those problems by formulating them as transformation regression problems. One problem involves finding ...