Analytic Functional Equations
brings the systematic method of Formal Power Series to bear on a wide variety of Functional Equations, enabling students in math contests to solve Functional Equations quickly and without the traditional guesswork. Also covered are Finite Difference Equations, and how to go from them to both Ordinary and Partial Differential Equations. A final chapter deals with a new definition of Functional Derivatives and solves several Functional Differential Equations of interest in Physics. A variety of new results are given in the book, and exercises and a large number of examples are presented throughout.