This may look like an afterthought, since I'm sticking it at the end, but, it isn't.  This stuff is really important -- I just didn't want to interrupt the flow of the zeros lessons.

Check out this graph:

You've got an ant climbing on the graph.  Not just any ant...  Pierre the Mountain Climbing Ant!

(He's kind of a pathetic math superhero.)  For this, the rule is that Pierre only crawls from let to right (like we read):

If Pierre is climbing uphill, then the graph is increasing:

So, our graph is increasing on

(we use interval notation with X VALUES!)