This is an archive of past discussions about Subgroup. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page.
I think it is the same as with a set. A proper subset Y of X is a subset Y which does not equal X. So, unless the group is trivial to start with, its trivial subgroup must be proper. No? Oleg Alexandrov (talk) 00:09, 9 October 2005 (UTC)
I think I have seen both, but what Oleg writes is what I would guess is the most common. It needs a survey of recent literature. People write "non-trivial proper subgroup" when they want to make sure there is no misunderstanding. --Zero11:07, 10 October 2005 (UTC)