Wolfram Research
Wolfram Math World: Ode With Constant Coefficients
This math site discusses how to solve a system of diferential equations.
Interactive Mathematics
Interactive Mathematics: 2nd Order D Es (Damping)
The use of differential equations to work electrical circuit problems with damping is demonstrated. Several examples are provided, along with detailed solutions. The fourth example includes several alternative solutions.
Interactive Mathematics
Interactive Mathematics: 2nd Order D Es (Forced Response)
This lesson covers constant, natural, and non-constant forced responses. Very detailed examples are included that work the problems step by step, with graphs, to assist in visual understanding.