# PrefacePreface

This text is intended for a one-semester undergraduate course in ordinary differential equations.

There are additional exercises or computer projects at the ends of many of the chapters. The computer projects often require a basic knowledge of programming. All of these exercises and projects are more substantial in nature and allow the exploration of new results and theory.

Sage (sagemath.org) is a free, open source, software system for advanced mathematics, which is ideal for assisting with a study of ordinary differential equations. Sage can be used either on your own computer, a local server, or on SageMathCloud (https://cloud.sagemath.com). The Sage code has been tested for accuracy with the most recent version available at this time: Sage Version 7.3 (released 2016–08–5).

Thomas W. JudsonStephen F. Austin State University

Nacogdoches, Texas 2016