Introduction

There are four major areas in the study of ordinary differential equations that are of interest in pure and applied science.

Exact solutions, which are closed-form or implicit analytical expressions that satisfy the given problem.

Numerical solutions, which are available for a wider class of problems, but are typically only valid over a limited range of the independent variables.

Qualitative theory, which is concerned with the global properties of solutions and is particularly important in the modern approach to dynamical systems.

Existence and uniqueness theorems, which guarantee that there are solutions with certain desirable properties provided a set of conditions is fulfilled by the differential equation.

Of these four areas, the study of exact solutions has the longest history, dating back to the period just after the discovery of calculus by Sir Isaac Newton and Gottfried Wilhelm von Leibniz. The following table is given as an introduction to the types of equations that can be solved by DSolve.

Examples of ODEs belonging to each of these types are given later in this section.