What formulas define these functions?
2 questions for you:
1.) Have you tried looking them up?
2.) Is this for your schoolwork?
1) Yes, I've tried looking them up. All I've found, however, are conceptual explanations of what they are and, occasionally, vague and dubious references to limits.
2) Of course not. If my school assigned interesting problems like this, I'd get more out of doing them than hanging around math forums... Heh. No; I'm just curious, because they're exceedingly useful and I'm beginning to understand enough mathematics that I might find the formulas somewhat intelligible.
You should try Google.
Well, it's not so obvious from where I sit. It looks suspiciously like a question that a student would ask to avoid trying to find the definitions on his own. I'd be remiss if I didn't ask.
Oh, I didn't think of wikipedia... Thank you!
Yeah, I should of mentioned what I did: At the end of my Google search string, I typed the word "wikipedia".
The strings I used were:
absolute value function wikipedia
floor function wikipedia
For math, wiki is great. I'd be wary of the physics entries though, because there are some cranks out there who edit the pages to push their own agendas.
In the future, don't forget MathWorld as a possible reference
Separate names with a comma.