If $f\in H^2(\mathbb R^2)$, I want to show that
$||f||_{L^\infty}\le c||f||_{H^1} [1+\ln(1+||f||_{H^2})]$
How can I get the "ln"? and how can I make it into a product of $H^1$ and $H^2$ norm?
It is actually one of my Real variables's project. So how can I do this inequality in an relativly "elementary" way?