Talk:Subgroup is Normal iff Contains Conjugate Elements

I fail to comprehend why this is separated from Subgroup is Superset of Conjugate iff Normal; it is filling in the def'n of subset. --Lord_Farin (talk) 22:44, 28 September 2012 (UTC)

So many source works themselves separate them out. The usual comment is that this is the most directly useful tests for normality as it provides a relatively quick technique to determine whether a sg is normal or not. Yes of course it could / should be proved directly by subset definition, I just haven't bothered.

There are as many ways to introduce normality as there are maths books. Most of them are clumsy and contrived. Such is life. --prime mover (talk) 05:14, 29 September 2012 (UTC)