# Wave equation

1. Mar 11, 2008

### n0_3sc

1. The problem statement, all variables and given/known data

I need to solve the following wave equation:
$$[\nabla^2 + \frac{\omega_a^2}{c^2}\epsilon]\mathbf{E_a} = -\frac{4\pi\omega_a^2}{c^2}\mathbf{P}^{(3)}$$

2. Relevant equations

$$\mathbf{P}^{(3)}=\chi^{(3)}:\mathbf{E_1E_1E_2^*}$$

E_1 and E_2 are two electric fields with different frequencies.

3. The attempt at a solution

I'm not sure how to attempt the problem. A starting point would be good.

2. Mar 11, 2008

### NoobixCube

we like to see an attempt before we give helpful hints...

3. Mar 11, 2008

### n0_3sc

NoobixCube read the last line of my post.