This is a question from a problem set on group cohomology, a subject I've just begun to learn.
Let $B$ be a finite group and $A$ be abelian. I am looking for two groups $G_1$ and $G_2$ such that $G_1$ and $G_2$ are isomorphic as groups but $1\rightarrow A\rightarrow G_1\rightarrow B\rightarrow 1$ and $1\rightarrow A\rightarrow G_2\rightarrow B\rightarrow 1$ are not isomorphic as extensions.
It has been suggested that I use $A=C_3^2$ and $B=C_2$. However, since the orders of $A$ and $B$ are relatively prime in this case, doesn't the Shur-Zassenhaus Lemma guarantee that the sequence splits so that there is only one extension? If this is the case, then how could we produce two non-isomorphic extensions? If someone could point out where I'm confused, I'd be very grateful.
Thanks.