Distributions. Let \(k(x,y)=\frac {1}{2\pi }\log \lvert x-y\rvert \), where \(x,y\in \mathbb {R}^2\).
- Show that \(k(\cdot ,y)\) is a distribution on \(\mathbb {R}^2\) for each \(y\in \mathbb {R}^2\).
- Show that as distributions, \(\Delta _x k(x,y)=\delta _y(x)\) for all \(y\in \mathbb {R}^2\). [\(\delta _y(x)=\delta (x-y)\) and \(\delta \) is the Dirac delta function.]