Categories

A
Algebraic Curves and Surfaces
B
Combinatorical Geometry
C
Topology
D
Kinematics and Mechanics
E
Differential Geometry
F
Algebra
G
Analysis, Probability Theory
H
Theory of Functions of Complex Variables
J
Differential Equations, Wave Theory
K
Geometrical Optics
L
Instruments and Devices.
M
History of Mathematis and Astronomy
Z
Other

Differential equations are equations which contain a function and it's derivatio(s). They describe standard phenomenons as movement. Expension and oscillation can be described and analysed by partial differential equations.

Differential Equations, Extension and Oscillation Processes, Wave Theory