My name is Hossien Sahebjame. I hold a BS, MS in pure mathematics from UCLA, CSULB respectively and have experience in a math PhD program. Currently I teach as a college mathematics professor and own/operate the math education collective MyMathYourMath. For better or worse I have authored a user friendly textbook on calculus more or less to explain it how I feel it should be explained. It is part I of III for Calculus I-III. In my spare time I'm either hiking, riding my unicycle, or in the water. Other than that I'm with my significant other and our three beautiful daughters. My own research interest involves the theory of integrating differential forms along compact Riemann surfaces, i.e., complex geometry/manifold theory. Qualifying exams at masters and PhD level I have successfully passed: Topology, Real & Complex Analysis, so I am considered an analyst as apposed to algebraist though there is sprinkles of ring and group theory in complex geometry. Has a BS, MS in pure math from UCI, CSULB respectively with experience in a PhD program. He specializes in Category Theory & PDEs. He did some editing as well as the cover art.