This question asks to show that U(10) != U(12). Could anyone explain to me how
o(9) and o(1) came about in the example.
9 and 1 were chosen because they're both perfect squares and elements of U(10). I think they're making it more complicated than it needs to be. All elements of U(12) have order 2 (except for 1 which has order 1). But 3 (in U(10)) does not because 3 squared is 9 which isn't 1 in U(10), so U(10)!=U(12).
--Dfreidin 15:02, 9 October 2008 (UTC)
