Help me please with this question.
Let's $\Delta u>0$ in connected domain in $\mathbb{R}^{n}$. Is it possible that function $u$ have local minimum? Can you show an example?
Thanks!!
Help me please with this question.
Let's $\Delta u>0$ in connected domain in $\mathbb{R}^{n}$. Is it possible that function $u$ have local minimum? Can you show an example?
Thanks!!
$f(x,y)=x^2 + y^2$ on all of $\mathbb{R}^2$