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#176 Re: Help Me ! » Maths Paper (Remarking Advice)... » 2011-08-25 05:34:18

I think, also, that bobbym is right - there is far more to life than A-levels - and even if you don't come to realise that, then they will soon take their toll and you are likely to end up pretty disenchanted with the whole thing. You are clearly an academic and you enjoy studying and learning for its own sake, so you should keep that up, but you should also take some time to relax and socialise - that's very important. You can do public speaking as an extra-curricular activity; you can just do it for fun - perhaps there is a club or a society which you can join within or without your school. It is important to do these things which you enjoy as well.

And no - you aren't boring smile

#177 Re: Help Me ! » Maths Paper (Remarking Advice)... » 2011-08-25 05:30:33

The points could be UCAS points - but I didn't think that UCAS points were awarded for GCSE - perhaps this is a new addition - I am not sure about those points, none of my GCSE results came with points.

I think whether you can take a subject at A-level without having a GCSE depends upon your school - my school would have allowed it, but it's obviously very very difficult for you to do so.

I think that those are incredible results and you should be very proud. You have done very well and shouldn't worry about what courses you take next year - with results like that you can definitely do well in biology - remember that you yourself said you could have done better were it not for your coursework. Anyway, universities are unlikely to make you an offer based on more than three subjects - possibly four, but not five or six, so you can afford to drop to a B in biology. Now, I've never heard of universities specifying three subjects - you may get an offer excluding one subject, or specifying an A/A* in a specific subject (e.g. maths for maths, or biology for medicine) but I can't see why any university would offer a mathematician or a physicist an offer requiring an A in biology. My friend was offered ABB with an A in geography to study geography with Chinese studies. He got AAB with a B in geography and missed the A by one mark. He did fail his offer, but he got a remark and made it. So yes, sometimes you will get a rigid offer which is subject specific - but I can't see why biology would be a problem for you.

I know a lot of people who missed their grades for Cambridge - including one who failed his STEP offer and one who missed his grades for classics, but they still got in. There are a lot of horror-stories, maths is a difficult and competitive course - as is physics - and nobody's saying that it will be easy; but I really do think that you're worrying unnecessarily - if you're seriously considering doing six A-levels, then that is really quite something and I think that you'll be fine. The highest offer I've heard of is 2 A*s and 2 As and that was this very competitive year - the last year of £3, 000 tuition fees, when lots of people will want to be going this year, instead of taking a gap year.

#178 Re: Help Me ! » sinh x » 2011-08-22 13:56:49

Hmmm, thanks gAr - I think you may well be right about that one.

Okay, well, can I ask some advice on phrasing. I'm writing an introduction to hyperbolic functions, and I'm analysing the graph of y = sinh x. Two of the features which I want to bring out are:

And:

Since I am talking about the graph, it's really important to me to bring out the fact that for large, negative values, sinh x approaches that function (1/2e^(-x)). I could just leave it in words, as I have it here, but the trouble is, when it comes to explaining why the graph of y = tanh x has asymptotes at y = 1 and y = -1, I am going to have a very confusing sentence or two, so what I'd really like is some advice on how to phrase it. I was going to use the limits notation I had all the way back up in post 1, but I'm not sure if that's the best option, so I tried the asymptotic equivalence notation we've just been looking at - but that doesn't seem to work that well either. I think you're probably right, gAr, but is it likely to be that well understood or commonly used?

So, what do you guys think? Should I just leave it in words and sacrifice the simple sentence structure?

Thanks smile

#179 Re: Help Me ! » Maths Paper (Remarking Advice)... » 2011-08-22 13:00:55

I think both of our esteemed bobs have given great advice. The best thing you can do is just enjoy your maths for yourself and if people think you're getting dumber - what does it matter? They will be wrong, of course, but even if they're not, does it really matter if you're still enjoying the maths that you're doing? The thing is, when we are younger our brains are designed for soaking up information - I'm not a neuroscientist, so I don't know, maybe learning does become harder as we get older, maybe we do forget things - but we're always learning. Maths is an incredibly broad discipline - and it's always growing. We can never know all of the maths that there is to know and we can always learn new maths and build on the old maths we've learned. I don't think we peak at 21, I mean, you'd have to know an awful lot of maths to be at your best then - surely more than anyone could learn in 21 years. And hey, I can't remember during which years Oliver Cromwell was Lord Protector of England and I learned that, what, five or six years ago, but it doesn't matter, because I can remember de Moivre's theorem. I think we tend to forget what we don't use, whether we're 21 or 101, but we can still pick it up again if we have to and keep going with what we can remember.

I think the bobs are right though - as I said at the beginning. Some people used to consider me a bit of a maths wiz in my class, but I was never considered the acid test for whether a problem was doable, but either way, I mean, I do the maths I do because I enjoy it and if people think I'm really good, then that's awfully nice of them to think so and say so - although it's not particularly true - but whether they do or they don't - and if they tell me I'm rubbish - it's not gonna stop me doing and enjoying the maths I can do. And I think that's the attitude to take to your studies. I have self-taught a fair bit - and clearly so have you. It can be done, but studying maths at school and university is a very useful way to learn the maths - so see it as a chance to learn more maths and to have fun, rather than worrying about how well, or not, you're doing. That's my advice anyway.

The best suggestion I've heard so far, though,is bob bundy's that you become a member - I think we'd all be richer for having you.

#180 Re: Help Me ! » Maths Paper (Remarking Advice)... » 2011-08-21 01:11:53

'The road to wisdom? Well, it's plain
and simple to express:
Err
and err
and err again
but less
and less
and less.'

I do know who said that - Piet Hein.

#181 Re: Help Me ! » sinh x » 2011-08-20 11:14:31

Okay, thanks everyone smile

On a related note, if you can express the idea that:

As:

How would you express:

Thanks smile

#182 Re: Help Me ! » Maths Paper (Remarking Advice)... » 2011-08-20 08:41:33

Well said Bobbym, I don't really have much to add to that. I don't think that there's any reason to suspect that you won't become a fantastic mathematician, but you don't need to be better than all the rest to have a good time doing the mathematics that you love.

And yes, it was indeed Edexcel. I quite like Edexcel tongue.

#183 Re: Help Me ! » Maths Paper (Remarking Advice)... » 2011-08-20 04:28:58

I am quite sure that if they had had your background these brilliant people would not have struggled, but that is very much the point - you are not below average, very few people have had your background, you are far above what one would really expect.

I'm sorry, I know very little Galois theory, I merely know of it, I was told that it was something which is well worth learning, though. It seems like quite a good resource, though, I may have to have a proper read of it soon. I'd really like to finish FP3 first, though smile

#184 Re: Help Me ! » Maths Paper (Remarking Advice)... » 2011-08-19 13:39:06

No, you didn't sound insulting at all smile I just hoped to make the point clear.

Yes, it's a rather famous poem. I can't remember who it was by, or I would have given it an author - I once saw it signed anon, but I read that it has been attributed to Author Napoleon Hill, so let's go with that.

Basic Galois theory is said to be very beautiful and, I'm sure, once you see how it's done, it's not that bad, but it's quite a target - it is not easy to self-teach something like that, so early on.

Well, it's good to be focused on your goals, but it's better to enjoy the process, the important thing is to enjoy the maths you're doing and enjoy the life you have whilst you still have it. It is unwise to become too focused on targets and forget to enjoy the process of getting there, so, if you've had a good time reading about it, don't worry if you haven't quite got it yet, because you will do.

I don't know you at all and so I can hardly judge, but you seem to have an incredible knowledge. There are good people, bright people, people who are, as we speak, preparing to be doctors in my year who have struggled their way through C3 - and when I say that, I mean really have found it difficult and that's not a sleight on them at all.

Mathematics is a beautiful subject and people can do amazing things with it, but they have all had to start somewhere, they have all had to learn their stuff to begin with - they are experienced mathematicians - who have learned from good people and if you follow your dream then you can too. If you do not, you will always be wondering what if.

#185 Re: Help Me ! » Maths Paper (Remarking Advice)... » 2011-08-19 13:16:38

He is the sort to just take something up and run with it. He just seemed to do it because it seemed like an interesting thing to do - I wouldn't advise it as such, but I don't think they'll consider you to be bs-ing unless you go about your interview in the wrong way.

Why are these unlikely goals? People do it - why can't you? Why do you think that people will be better than you? You are clearly a talented mathematician, with knowledge far beyond what is expected. Think about STEP - all of the prerequisites are on C1-C4, I believe, certainly most of them - I believe. I don't think it's about breadth, it's about talent, and understanding of mathematics. You can go very far, but you have to have some faith in yourself. I don't want to sound like a motivational speaker, or a life coach or something - they tend to annoy me anyway, but:

'If you think you are beaten, you are;
If you think you dare not, you don't.
If you'd like to win, but think you can't
It's almost a cinch you won't.

If you think you'll lose, you've lost.
For out in the world we find
Success begins with a fellow's will:
It's all in his state of mind.

If you think you're outclassed, you are:
You've got to think high to rise,
You've got to be sure of yourself before
You'll ever win that prize.

Life's battles don't always go
To the stronger or faster man,
But sooner or later the man who wins
Is the one who thinks he can.'

Anyway, yes i^i is very straightforward - but quite nice, I enjoyed doing it myself. Interesting that it should be real, don't you think? But the point wasn't that it was hard, but that it was just an interesting thing for him to do - and it's important to show that you care and that you are special, perhaps more so than just some letters.

#186 Re: Help Me ! » Maths Paper (Remarking Advice)... » 2011-08-19 12:47:18

Hmmm, well I'm pleased to see that you're not naïve, but there are a lot of horror stories out there which - in reality, in the general case, just aren't really that bad. I don't think that they will think that you are jut bs-ing your interview, if you just behave naturally, like you would if you were discussing maths with a mathematician - which is what you will be doing at the end of the day. I have a friend who - during his physics interview - decided that since he had nothing else to ask at the end of his interview at Imperial, I think, although it may have been another, just derived i^i for his interviewer.

Oxbridge interviews are famously hard, that's the point, but if you are genuinely interested - which I know you are - then it should be right up your street. I assume you know the answer to that derivative, you would just have to talk your way through it. Anyway, even if you get it wrong - they're testing how you think - if you reason through it, you can still impress.

No, nothing is free, I'm afraid, but I can't urge you enough to chase your dream. Even if you have to work hard for it, if you love it, then you really will reap the rewards. Why couldn't you just continue at university - you could lecture? Do you have any ideas about what you'd like to do in future? It's not necessarily an easy life, but it's far more enjoyable and when you go to meet your maker you can go with your head held high - proud of a life well-lived doing what you love and believe in. That's gotta be better, hasn't it?

#187 Re: Help Me ! » sinh x » 2011-08-19 12:12:19

I believe that you are indeed both right. I was looking at the graph of y = sinh x, though, which, for large, negative values of x, approaches the graph of:

As we can see, because:

Now, my textbook wrote:

But I really didn't like this way of putting it and I quite like limits and asymptotic analysis and such areas and so I thought I'd try to make use of them, but we don't cover them in much detail and I have limited (poor pun) experience of using minus infinity, so I just wanted to check that this was a valid way of expressing the idea.

#188 Re: Help Me ! » Maths Paper (Remarking Advice)... » 2011-08-19 12:04:56

I didn't resit C3 and C4 because I took them this June and I made my offer so there is no need lol smile

I was not interviewed by SOAS, so unfortunately I can't help you, but general interview technique is what would matter I think. Just relax, talk through your reasoning - especially at Cambridge, they're looking for people who think in the right way and have interesting opinions. Clearly you are somebody who is interested in maths - so let that come across, show your enthusiasm, engage in a discussion, like you would with the people on here. It's almost something you can look forward to - if it didn't mean so much to you, I think that if you do it right, then it's something that you would otherwise rather enjoy.

It may be optional, but I know a lot of people who filled this form out, so I assumed that it was compulsory, at least for certain subjects. Perhaps I am wrong about this, but I can only assume that it will help.

Well, this isn't the place for a political rant, but I very strongly disagree with the government's policy here, but let's not get drawn into politics. I have a great interest in the subject, but there's a time and a place lol smile. However, you will be aware that you do not have to start paying this money back until you can afford to and a good degree should help you to achieve a reasonable salary. Honestly, though, I know it's easier said than done, but the reality is that the money isn't what matters. 'Find a job you love and you'll never have to work a day in your life' in the wise words of Confucius, unless I'm very much mistaken. The money doesn't have to be paid back immediately, so I think you should follow your dreams. You seem to be somebody with a passion for mathematics - follow it through, or you'll regret it. What difference does a few million make on your death bed - but if you can look back at a life like that of Erdős - look back on everything you've done, the contributions you've made, pursuing what you love, then I would say you are far better off.

#189 Help Me ! » sinh x » 2011-08-19 11:45:48

Au101
Replies: 8

Hi, I have a question about the sinh function. Is it true that:

Thanks smile

#190 Re: Help Me ! » Maths Paper (Remarking Advice)... » 2011-08-19 11:09:34

The grade boundaries for C4 in January are correct - hence my paper this year was supposedly quite hard.

If you wrote what you said you wrote I would be surprised, if you lost marks. however, my teacher said that she spoke to the board, and unless it's a bit of a shock-tactic from her, that is the case. Anyway, even if they don't actually take marks off, it can only help make your answer clearer. It's a bit of a pain, especially in timed conditions, but it really will help you. You should definitely make it clear which part is which. Answer to part (b) = is exactly what I was always told to write. And obviously, beware units.

Well, it's your thread, so I assume it doesn't really matter if we wander off on a tangent.

I am going to SOAS (School of Oriental and African Studies - which is part of the University of London, in Russell Square) to do Sanskrit. My offer was ABB and I got A*AB (with the A in (single) maths. Which came as a disappointment to me, but I know that exams can go badly for me and it doesn't affect my attitude towards maths. It's just that I know that I could do every question on that paper, so clearly I did something silly, which is frustrating to know, but that's life for you.)

I took Government & Politics (which I dropped at AS), Religious Studies and mathematics. I wasn't interested in maths at the time, and very nearly didn't take it. But since I started to enjoy myself doing additional maths (or add maths, its a pre A-level qualification, which basically covers most of C1) I decided to take it and have since become quite enamoured with it. As a result, I didn't take further maths, and although I do regret this in many ways, I don't really mind, because I've spent my holidays doing FP1 and FP2 and am just writing up a chapter on the graphs of hyperbolic functions as we speak, so at least it's given me something to do. Anyway, I've never liked applied maths, so at least I can avoid doing those modules.)

In maths I got:

C1: 100
C2: 87 (ran out of time on that one lol)
M1: 29 (which is a U, I told you I don't like applied maths, lol) resat and got 96
C3: 80
C4: 76 (bit disappointed in the last two, I'm not sure where the marks really went, but hey, like I say, that's life.)
M2: 76

Happily (in the case of M1) for the UCAS form you don't need to put your module scores down. Well, I didn't. Cambridge does, however, specifically ask for them. I assume if you give the 100 after 100 that can only help, but I think it's STEP that they're really interested. In fact, they've been known to not really look at your other exams, but that might be a bit of a myth. I did, however, get an offer from King's College London to study philosophy with 2 Bs in GCSE English and a personal statement which didn't mention a single extra curricular activity. The reason for this was because I took a very different line to my personal statement. So yeah,I think the other thing is to really work on an individual personal statement and an individual interview. You are gonna need grades to go to Cambridge, that's just the way it is, we can't dance around that. But what they really like is someone who obviously cares, someone a bit special. Don't just tick boxes on your UCAS form, don't come across as just another, one-dimensional student - show what a special talent you really are.

So yeah, I don't think the marks are everything, but they can only help you, I wouldn't be complacent about it, you've got big dreams and anything that can help you you should go for, but I wouldn't get too bogged down in one mechanics module. Whether it's worth the money, only you can decide, but and this is only my humble and probably quite ill-informed opinion - I would be surprised to see it change.

#191 Re: Help Me ! » Maths Paper (Remarking Advice)... » 2011-08-19 10:50:37

The scripts themselves will not be marked in any other way, I mean, the person marking wouldn't know nor care. There's a bit of a conspiracy theory that in the case of subjects where the January paper is only for resits, the paper itself may be more difficult (although I highly doubt that) but since this isn't the case for maths it doesn't matter at all. I'm not sure what year eleven is (I go to a school with very odd naming conventions, and we had fifth form, lower sixth and upper sixth (which is slightly more normal than the names for previous years)) but am I right in thinking that that's GCSE year. Even if it's AS year, doing the resit will probably not hold you back, because you seem to be accelerated in some way. Nevertheless, some universities don't look kindly on resits, I have to say, in fact I think there are some which won't accept A2 resits. I don't know about AS's though. I'm not really a higher education adviser, I think talking it over with that person is your best option, but I think, if you want to apply for maths at Cambridge, there are more important things than module scores. First of all, you definitely need to do double maths and secondly, STEP. You may or may not know anything about STEP, but it is very very hard, and a typical maths offer will be a 1, 1 in STEP II and III. This is incredibly hard. I know two people at my school last year - one of whom had four A*s - who failed their offer, getting a 2 in STEP III. This is where I would recommend you invest your efforts, especially as this is the real distinguisher.

#192 Re: Help Me ! » Maths Paper (Remarking Advice)... » 2011-08-19 09:34:47

Also, re-reading your conversation from earlier, they cannot penalise you for doing (b) before (a), some questions can be done in any order, especially if you have simultaneous equations and then it's just a choice if which unknown you find first. This is often the case in questions involving F = ma. Often this is specifically pointed out on the mark schemes. Sometimes, however, a poor, tired examiner will not notice. For this reason it is always advisable to number clearly. If you have found the answer to part (b) without realising it, you should go back, change your numbering from (a) to (b) and clearly write:

Answer to part (b): {underlined answer}

And then continue with the question, clearly writing

Answer to part (a): {underlined answer}

Another thing which I have just remembered is that the board has recently said that they will take marks off for not making your answer clear. This is no word of a lie, my mechanics teacher specifically said that any abbreviations must be expanded. I am told that it is no longer acceptable (at least in M2) to write, for example:

m = 2.

You must write:

Therefore, the weight of the boy at point B = 2 kg.

For example. Even in the case of simple abbreviations like, m for mass and a for acceleration. This is mainly because people use different abbreviations, and if you've used arbitrary variables, it can become confusing. Anyway, this is good advice for next time, even if it isn't the cause of your lost marks this time. It's a pain, but it is good form.

#193 Re: Help Me ! » Maths Paper (Remarking Advice)... » 2011-08-19 09:29:04

Hello, zetafunc, I resat that paper myself. I have to be honest with you, I did score in the nineties - although I'd be interested to see what my mistake(s) was/were - but in my C3 and C4 modules, I was disappointed, having expected to score significantly higher. It doesn't matter to me, I am off to my first choice university next month, so all is well, but I hope that I can offer a constructive take on the situation. The first thing that I would say is that marks may be awarded specifically for correct working. I knew of somebody who happened, by chance, to get the right answer to a question, but his method was wrong. I believe that he had used an equation where a constant speed is assumed and the speed was not so. It was something similar to this anyway and - rightly, you might say - he was not awarded any marks. Is it possible that your methods were not correct? It can be difficult to remember exactly how you did something even straight after an exam. Are you also sure that you rounded correctly? Marks may be awarded for correct solution only, and you may have been a decimal place out in a question, or two. I tend to be fairly philosophical with my exam results, I am disappointed at my own performance in maths, but I am happy to accept that - in the stress of it all - I probably got the wrong end of the stick, or made a mistake in the working. What I've said above is to illustrate the fact that there can be myriad ways in which marks can go astray, especially in an exam situation and so I would advise that you ordered a photocopy and double-checked first. I seem to remember that this is possible, although if there is a problem with timing, you might have to get a remark, without checking first. Marks can go down, though, and whilst examiners can obviously make mistakes, they are moderated and maths papers can be marked very formulaically, so you're unlikely to see a large variation, as you might in an essay subject, where it is a judgement call.

With maths, of course, your results will average out, there are other modules and this is good and bad. Obviously, the higher the module marks, the better your position, so a remark would be advisable in that way. On the other hand, however, one module is not the be-all-and-end-all, a few marks here and there isn't the end of the world, especially as this is an applied module.

My advice, then, is to remember that in examinations, marks can be lost unexpectedly, which is a great shame and can obscure the real talent. As a result, I would personally order the photocopy of the script. If this is not an option, however, you can get the remark, it's not hugely expensive, but I would certainly not expect anything to come of having mine remarked. I wouldn't wish to say that the same will be true in your case, but I don't think I'd do it myself.

P.S. I don't think it is free to sit any examination, including re-sits. However, your school may be prepared to pay for you.

#194 Re: Help Me ! » Riemann Sums » 2011-08-16 01:15:09

I see, okay, I think I have it figured out, now, thank you smile

#195 Re: Help Me ! » Riemann Sums » 2011-08-13 03:43:16

Nono I think you're right, I'm just having difficulty explaining the jump from:

It seems to make intuitive sense in my head, that as n tends to infinity that is the integral which you will end up with. The thing is though, at my school you could do double or single maths. I did single maths which means I didn't cover what is known as further pure, which has a lot of interesting pure maths on it which I wanted to cover. So I got a textbook and have spent my recent holidays on the first two of three modules. My method has been to write myself my own 'sort-of textbook', which is more a sort of extended set of notes with various tangents and exercises and what I wanted to do was to explain this derivation. The thing is, it makes some sense in my head, but I certainly can't write-up an explanation without sort of waving my hands and saying, well it looks about right. tongue

#196 Re: Help Me ! » Riemann Sums » 2011-08-13 03:07:57

Sorry about the strange line breaks and my failure to get the LaTeX up originally, I had left in a hyphen as the minus instead of a a dash. That's the trouble with copying plain text in tongue

#197 Help Me ! » Riemann Sums » 2011-08-13 02:58:44

Au101
Replies: 7

Hi guys, I have a problem with understanding Riemann sums. I have read the wikipedia article on the subject and I can essentially understand what they are, my problem is with understanding a particular integral. The derivation which wikipedia gives requires a knowledge of Riemann sums which I don't seem to have and I would be most grateful if somebody could explain the derivation to me.

I have been working on polar coordinates and have reached the section on the area of a sector, which is given by the integral:

And the derivation of this integral is given by wiki as follows:

This I can understand, but the final part of the derivation I do not follow:

Is there anybody who could help to explain this last step? Thanks smile

#198 Re: Help Me ! » Differentiation Question » 2011-08-05 11:16:06

Hi Bob,

I agree and personally, I prefer to work out a solution by hand where it's feasible - it's more satisfying. I can post my full solution for you if you're interested - see if our methods have changed smile

#200 Re: Help Me ! » Differentiation Question » 2011-08-05 01:55:23

You're quite right, although I value your contribution as well. Nevertheless, I'm very grateful to you Bob, for going on and helping with the rest of the question, especially if this is not your area smile.

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