
Part one of the Principles of Differential Equations addresses topics such as introduction to differential equations, solving quadratic equations, theorems for integral functions, first principles of wave equation, moments of inertia, and operator functions on differentials. Part two consists of an introduction to real functions and derivatives, solutions to the equations involving complex numbers and derivatives. Topics include the formulation of functions and series, analytic functions and their solutions, and the use of integral curve models. Part three contains several easy problems involving the use of multiple derivatives and uses real functions to solve differentials on the elliptic and spherical planes as well as surfaces.
Overall, the book is a quick read with many exercises to help the reader get the most out of the book. It is also a good reference for those who already know much about differentials and derivatives but who may have difficulties in interpreting a visual form to solve a differential equation. However, if you are a novice in the field and need to brush up your knowledge, I do not think this book will help you that much. For a novice, I recommend learning from more advanced resources or looking at more complicated tutorials on derivative and integral calculus exercises.