Verifying General Solution of 2D Poisson Equation

glmuelle
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Hi

Homework Statement


Verify, that

u(\vec{x}) := - \frac{1}{2 \pi} \int \limits_{\mathbb{R}^2} \log ||\vec{x} - \vec{y} || f(\vec{y}) d \vec{y}

is the general solution of the 2 dimensional Poisson equation:

\Delta u = - f

where f \in C^2_c(\mathbb{R}^2) is differentiable twice and has compact support.

Homework Equations





The Attempt at a Solution




My attempt would be to swap integral and Laplace operator but I know it's wrong to just do that...
Can anyone help me please? Thanks!
Gloria
 
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the Laplace operator is applied with respect to x, and the integration is performed over y -> I think you can swap them ( x is only a parameter inside of the integral)
 
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