Math for hackers.
bonsaitree: I'd recommend using this book as a rough guide:http://tinyurl.com/nfe3gvDon't let the title fool you.  It's really a guide to advanced applied mathematics.I'd also suggest the material be supplimented with a good bit of statistics.  In my experience, statistical reasoning (particularly as it applies to noise, perturbation, and system reliability) tends to be weakness with hackers.