Graphs is pretty straightforward, their might be graph questions on drawing f'(x) from f(x) or vice versa, or they give you a graph and you have to draw arctanf(x), arcsinf(x) etc. And some easy implicit differentiation, don't stuff up on the algebra.
Complex numbers isn't that hard, I doubt they'll put complex polynomials if you haven't done any polynomials yet, but be wary. The teachers may steal questions from past HSC papers, trial papers. Be sure to know how to graph complex loci, and show algebraically the cartesian equation of these loci.
Some vector questions might be in it, like as to find points using vectors. Check out some of the past HSC questions on this type, it's not very common but sometimes is a bit tricky
That's all I can think of right now. Good luck
Edit: We only had a complex number test for our first one