In my booklet, Option D in Question 9 was printed as |x|≥tan-1x which is true, not |x|>tan-1x (difference being it has a greater than or equals sign, and thus the equality at x=0 doesn't make it false).
Ahh I misinterpreted the question quite badly then :L
Yep, okay, with this, I managed to solve the problem. Got stuck with rgV02cosθ = rg(V12 - V22) - (V0V2)2sinθ for a while, though. That was rather tricky.
Holy moly I just realised an almost identical question came up in my half yearlies and I lost a couple of marks over it. Thought I'd learnt from that mistake, but apparently not. (for anyone's that wondering, it's just using the basic angle subtended by arc at centre = twice the angle subtended...