# Homework Help: Differential equations

1. Nov 17, 2006

### Logarythmic

How can I solve the two differential equations

$$p(x)y''(x) + q(x)y'(x) + a \sin{y(x)} = 0$$

and

$$ay''(x) + p(x)y(x) + b \cos{y(x)} = 0$$

?

Are there any general method for solving an equation of the form

$$p(x)y''(x) + q(x)y'(x) + r(x)y(x) + a \sin{y(x)} = 0$$

or the similar one with cos instead of sin?

Last edited: Nov 17, 2006
2. Nov 18, 2006

### arildno

Yes, many. All of them belongs in the topic of numerical analysis.

3. Nov 18, 2006

### Logarythmic

Yeah, but I've got a problem where I'm supposed to solve the first two analytically...