My Schools estimate was 98, other's say 96/97, I really have no clue as to what i'm truly aiming for, my course is only 95, thus I'll be content with anything above 97 :)
you let whats inside the bracket=alpha or whatever, then you simplify, use a bit of pythagorean ratios, then you have double angle somewhere and then you simplify
Tumbleweed............................................................................
:), as you can see not many people are keen on estimating an ATAR with a school rank of such magnitude (300+), it is very hard, so it would depend heavily on how you perform in the HSC, as of now I'd say high...
For those who still don't get part b), here is my solution that I used in the exam:
Sorry if there are some minor mistakes, I did this in like a couple of minutes.