Fundamentals of Differential Equations presents the basic theory of differential equations and offers a variety of modern applications in science and engineering‎.‎ Available in two versions‎,‎ 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.‎ Fundamentals of Differential Equations‎,‎ Eighth Edition is suitable for a one‎-semester sophomore‎- or junior‎-level course‎.‎ Fundamentals of Differential Equations with Boundary Value Problems‎,‎ Sixth Edition‎,‎ contains enough material for a two‎-semester course that covers and builds on boundary value problems‎.‎ The Boundary Value Problems version consists of the main text plus three additional chapters ‎(‎Eigenvalue Problems and Sturm‎-Liouville Equations‎;‎ Stability of Autonomous Systems‎;‎ and Existence and Uniqueness Theory‎)‎‎.‎