Just out of curiosity: If $G$ is a topological group and $H, K$ are closed subgroups, is $H\cdot K$ a closed subgroup?
Thanks!
Just out of curiosity: If $G$ is a topological group and $H, K$ are closed subgroups, is $H\cdot K$ a closed subgroup?
Thanks!
No, take $G$ is the group of real numbers $\Bbb R$, $H$ is $\Bbb Z$ and $K$ is $\Bbb Zx$ where $x$ is irrational. The group $H.K$ is dense.