FRIENDS, I AM A STUDENT OF CLASS XII. RECENTLY WE HAD A FIITJEE AITS (WHEN WE WERE IN XI) AND THE MATHS SECTION WAS ULTRA TOUGH. MAXIMUM SCORE WENT ONLY UPTO 30% IN MATHS. WHERE CAN ONE FIND THE THEORY FOR SUCH QUES? ANYBOOKS FOR THESE QUES?EVEN FIITJEE PACKAGES ARE VERY DIFFICULT! WHERE CAN WE FIND GOOD THEORY FOR SUCH QUES?

FIITJEE packages have sums of different levels. always free feel to ask quests here

You dont need to study any extra theory. . .
just try to strengthen your basics and solve as much question as you can
fiitjee aits is comparatively difficult than others so you need and worry
just give a "relatively" good performance and secure a good "percentile"

I am a fiitjean myself

All the best

Do not forget to approve :)