For one-semeseter sophomore- or junior-level courses in Differential Equations. Fundamentals of Differential Equations presents the basic theory of differential equations and offers a variety of modern applications in science and engineering. Also available in the version Fundamentals of Differential Equations with Boundary Value Problems, these flexible texts offer the instructor many choices in syllabus design, course emphasis (theory, methodology, applications, and numerical methods), and in using commercially available computer software.