union of non-re sets

From: Alex (alexk_at_mailinator.com)
Date: 01/17/04 

Date: 17 Jan 2004 08:16:18 -0800

Hi,

I was wondering,
Is there a possibility that a union two non-re sets, will give a
(non-recursive) re set ?
Or it is impossible, since intuitively, when you do union you just
make them "bigger", and do no minimize the thing that makes them
non-re ?

Thanks,
Alex