Non-abealian groups with order 8.

“Easy” proof that only two Non-abealian groups with order 8 exist.

Non-abealian groups with order 8 - easy proof   
https://docs.google.com/file/d/0B4hjJTbOj_agSU1GbkZsRWNseUk/edit?usp=sharing

read the whole proof in the link above  ---