Please take out a piece of paper, and proove that between every 2 rational numbers, there's an irrational number, and between every 2 irrational numbers, there's a rational number.
I still have nightmares about that class, even though I did get a 'B' in the class.
Mark
Our first homework assignment in non-Euclidean geometry was to prove 2 points determine a line. Oh, and the teacher thought having a textbook made the class too easy, so we had no reference material.
I love impossible homework assignments.