I am an aspiring mathemarician and wanted to know algebra/trig books with rigor. I have sullivan pre cal/ stewart/mcguie and these are extremely easy books. I enjoy the sullivan book because of its wide range of topics( introduction to vectors) but the exercises are extremely easy. The best pre cal book I own is by Cohen and the problems are harder then the other books I own. Yet I want to get a book or more that are more challenging then Cohen. Any ideas?