Think very carefully before deciding whether you want to do core or single maths. I'm not saying this to piss off HMK but I honestly think doing core was the worst decision I've made whilst being at Durham. Last term I'd be tempted to say core was on the whole better than single, this term? Absolutely not. Why? Well where do I start...
Ah yes, the probability course. Dr MacPhee is the worst lecturer I've had by a long, long way. He has the unusual gift of being incredibly patronising at yet utterly useless at explaining things. For the past 4 weeks I can honestly say I've understood nothing in his lectures, absolutely nothing. I read his notes and they still don't make a word of sense. His weekly problems are also beyond ridiculous. To put it in perspective last week I spent about 40 minutes to an hour on all the weekly problems for physics, for probability alone it took 3 days, and even then I didn't solve it! There is not a single mathematician I've spoken to who likes him or is finding the work reasonable, even those who are doing stats as a module are struggling! I could also have a good rant about my tutor who is just as useless but since there is a chance you could get a good one I'll ignore that.
Then there's algebra. Admittedly if you find pure maths interesting then I'm sure it's a fascinating course, however for me it doesn't float my boat at all and it's honestly horrific. I really couldn't care less about whether something group is abelian or not. The proofs are so pointless and dull it makes you want to cry at times. Admittedly the lecturer is good, he certainly has a passion for what he does, but it's not enough for me.
Oh and B1 is just a repeat of core A with a slightly more in depth look at some stuff. It's my favourite course in maths this term and is by far the easiest, but to put it in perspective on how bad things have got I thought this was the worst one last term.
Essentially if you see yourself as a mathematician then by all means go for core. If however you see yourself as a physicist (in other words you prefer to use maths as opposed to analysing it) then go for single maths. In a way I'm glad I got to experience core to see if pure maths would interest me but the answer is definitely no.