Let $G,*$ be a group and $A,*$ a normal subgroup of $G,*$: $$ A \triangleleft G \quad( \equiv \forall g\in G: gA = Ag) $$ Then $G$ is commutative iff A and $\frac{G}{A}$ are commutative.
I can see that the theorem is true in one direction $(\Leftarrow)$, but I'm not sure about the other. Any hints? Or maybe a counterexample...
This is false. $A_3$ and $S_3/A_3$ are both abelian, but $S_3$ is not.