I loved higher physics (uni) compared to HSC level, none of that memorising syllabus dot points rubbish (I was never good at waffling on with those long response questions in the HSC). At uni it's true physics with proper mathematical problem solving questions. Believe it or not I found 3U & 4U maths helped more for higher physics than HSC physics did! (goes to show how poor the HSC physics curriculum is)
If you've only done 2U maths in the HSC, you should be ok for maths 1A & 1B, provided you put in the "hard yards". A bridging course would most certainly help. If you've done extension maths, then maths 1A and 1B shouldn't be difficult. Uni maths is divided into Calculus & Algebra. Calculus is mostly about functions, limits, differentiation/integration, convergence, differential equations, taylor series etc. Algebra mostly is about complex no's, vectors, matrices, subspaces, statistics & probability etc. I personally found calculus easier since it was more similar to HSC maths.
I wasn't a fan of discrete maths though, especially at first since it was all foreign and weird stuff that you haven't seen before in the HSC (bar a few topics like induction). Once you get used to it though, it's not too bad (the real challenge is getting "used to it" before the exam!
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