its not that hard thats why the competition is very tough to be ranked 1st or 2nd because some people work their asses off for sacs but if you don't at least look through your notes before sacs, surely there will be stupid mistakes. Further maths is about practising and avoiding stupid mistakes. I got 43 for further and would say i dropped 3 marks in 1st exam and about 4 in the 2nd and was ranked 3/70 in the school for sacs.
It's the silly mistakes that kills you in further, not the difficulty of the subject. You are too careless because it's way too easy.
I did it without a textbook all year as well, only borrowed a textbook from library to take into the exam.
And as modules go, you don't have to do the one the school does but you got to do it in the sacs though. But in the exam i didn't do business maths i chose matrices instead which is all calculator work.