(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Prove that the quaternion group ##Q_8## is not isomorphic to a semi-direct product ##H\rtimes_\rho K## for non-trivial groups ##H## and ##K##.

2. Relevant equations

3. The attempt at a solution

My idea is to look at the subgroups of ##Q_8## and to show that the intersection of any two nontrivial subgroups is nontrivial. Is this approach valid? My only problem I think is showing that if ##Q_8## were to be isomorphic to a semi-direct product, then ##H## and ##K## must be subgroups of ##Q_8##. Is this true in general?

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# Homework Help: Showing that Q_8 can't be written as a direct product

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