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 <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.