[Math] Non-commutative quotient group

abstract-algebragroup-theory

If you have a non-abelian group $G$ with some normal subgroup $K$, is it possible to have a non-abelian quotient group $G/K$?

Besides actually sitting down and trying to generate quotient groups through exhaustion, I have been thinking about using the fundamental theory of homomorphisms to pick a small non-abelian group like $D_6$ and find the quotient group it is isomorphic to. Does this seem like a good tactic?

I'm not looking for answers, just confirmation that this is a useful way to be thinking about it.

Best Answer

In general, there is the following fact:

If $N$ is a normal subgroup of $G$, then $G/N$ is abelian if and only if $[G,G]$ (the commutator subgroup) is a subgroup of $N$.

So the quotient will not be commutative precisely when your normal subgroup does not contain the commutators.

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