I have to agree regarding getting the GMAT math guide. I had a friend who was taking the GMAT and I said I'd help her study. I had just finished up my fourth semester of calculus and thought I could be a great help. To prepare, I got a GMAT math study guide at the local library and was very impressed by the material. I wish I had gone over that material before taking calc in college. It would have made my classes much, much easier.