Many differential equations with nonlinearities or variable coefficients do not permit the construction of exact solutions. This text introduces several perturbation methods that can be used to develop approximate solutions of such equations.

Preface Asymptotic Series and Expansions Regular Perturbation Methods The Method of Strained Coordinates/Parameters Method of Averaging The Method of Matched Asymptotic Expansions Method of Multiple Scales Miscellaneous Perturbation Methods References Answers to Selected Problems Index Permissions