# Tag Archives: unipotent elements

## Extensions of Tori by Tori are Tori

Continuing our previous series, $G$ is an algebraic group over an algebraically closed field $k$ and we identify $G$ with $G(k)$. Here is an interesting fact: Theorem. In a connected solvable group the unipotent part $G_u$ is a closed connected normal subgroup of $G$ and contains the commutator subgroup […]