I'm not saying that you will be able to get a good sound with one mic, but you certainly will be able to learn a lot about mic placement if you mess around with it a bit, play with different positions in the room, miking at different angles to the drums, different distances etc. Common sense rules apply, the closer you are to one drum the louder it will be, the more directly the mic points at something the more high end it will pick up from it. Moving the mic back will usually give you a more realistic sound up to a point and then it becomes very 'ambient'.