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

Prove that D4 (Dihedral group) cannot be expressed as an internal direct product of two proper subgroups.

2. Relevant equations

3. The attempt at a solution

I know that the only two possible subgroups would be the subgroups of order 4 and 2. I am thinking since D4 is not commutative I can get a contradicition this way, but I am not sure how to do it. Any help would be welcomed

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# Homework Help: D4 question

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