Just did both Pilot and AEC in Trenton in one fun-filled week. Passed both, good times! As stated, no specifics, just show up well rested and be sharp! Never hurts to "dress for success" as confidence and feeling well-prepared are always good. Nothing specific you can study for. They're looking for inherent skill and aptitude for future tasks here... not how well you can fly or direct traffic. In our group they put everyone through both Pilot and AEC tests. It's challenging, but you'll enjoy it! Some passed both, most passed one or the other, and a few passed neither. Our group had 6/14 pass pilot, some with prior flight experience, some without.
Enjoy the trip on their dime. Accomodations are great, food is surprisingly good for an 'army base', people there are friendly and instructors are awesome.
I think others will agree that 'Personal prep' will do you much better than 'Math prep'. Stay fit, eat well, be rested. When I was just there I was up early every day and went for a run and shower before breakfast (for me it sharpens the mind)... then back to your room, dress up sharp and go rock it!
Above all, DON'T STRESS!! It's hard, but super-fun... kinda like a really good workout or a long hike, how you feel like a million bucks afterwards. Go do your best and you'll soon find out if this might be for you, or maybe not... Just ENJOY!!
'Greg.