Show that Q does not fulfill the completeness axiom.
"Every non empty set of rational numbers that contains an upper bound contains a least upper bound" (show this is false)
The Attempt at a Solution
I've sat on this question for a few days, but I can't think of ANYTHING. I tried thinking of trying to show the opposite, to see where it would lead me. I couldn't start there. Any help JUST getting started?
I understand what the completeness axiom is. I understand what rational numbers are. I have no clue how to start.