## Differential equations front page

### Quick description

Differential equations (DEs) are equations in which the unknown which one is solving for is a function, and the equation that is satisfies contains expressions involving the derivatives of the function, as well as the functions itself.

If the function is just a function of one variable (so that only derivatives in that one variable are involved), then we speak of an ordinary differential equation (or ODE). If the function is a function of several variables, so that partial derivatives are involved, we speak of a partial differential equation (or PDE).

In addition to being classified as ODEs or PDEs, differential equations are also classified by the highest derivative of the unknown function that appears (the order), whether or not they are linear in the unknown (linear vs. non-linear equations), and, in the case of PDEs, by more subtle considerations of the way that the various partial derivatives appear and are related to one another in the equation (so that one speaks of, for example, elliptic, hyperbolic, parabolic, and dispersive equations).

### Articles on Differential Equations

This page itself is primarily a navigation page, providing links to articles related to differential equations. We refer to the various articles linked below for a more thorough discussion of some of the concepts mentioned above, as well as other aspects of the theory of DEs and their solution.

An Easy Way to Solve a Simple First Order Differential Equation

Use Fourier transforms to calculate derivatives

Wick-type rotations Incomplete This article is incomplete. This page needs to be properly written and organized, with a more extensive set of links related to the various approaches to solving DEs.