Solve 2D Green Function: Star Equation

[PeteSampras]

Hello, i don't understand how i integrate the star equation at the figure.

Fot example $$\int d x_1 \int d x_2 \frac{d^2G}{d x_1}$$

$$= \int d x_1 \frac{d^2G}{d x_1} \int d x_2$$

but [tex][/tex]$$<b><b>\int d x_2 </b></b>$$
$$x_2|^\epsilon_{-\epsilon}=0$$ ...sure this is a error, but i don't understand how i find the answer $$2a\pi$$

 

[Svein]

1. I think you mean Green's function.
2. The integral - such as you have presented it - makes little sense. $\int_{a}^{b} dx_{1}$ = b - a. Also $\frac{d^{2}G}{dx_{1}}$ makes no sense.