See comments after each part  but who knows exactly what the markers think. Somewhere in range 6879 ?!? At top end of range should be a 1 in most years; at the bottom end of the range possibly might be 50/50 depending on the overall level of the paper. This seems mixed from comments some people loved it, some hated it  too difficult to call.(Original post by hassi94)
Hey  thought I might ask you:
I got the ln(1+x) one fully done and perfect as far as I can see so I'll say 20
20
As well as this; I did the above which you quoted so we're in agreement at about 10.
10 (30 running total)
I also did the first question (binomial) but as far as I remember I did the first bit, I did x^24 in the first bit but I can't remember if my method was correct or not (I assume so as I got the right answer and I'm pretty certain I didn't try just to 'fit in' an answer)  and then did x^25 right (though that was barely worth a mark probably). I got x^66 wrong because I summed all the triangular numbers required, rather than doing 2 times all but the last. I did however use the correct triangle numbers.
Say 1317 depending on whether marker believes you understand exactly what you were doing (43  47 running total)
I also did the integral question where I got everything except for didn't finish the last part. I had pretty much gotten it at f(x+sqrt(x^2+1))  in fact I had at one point, then got to and wrote 1/t^2 + 1/t^4, thought it was wrong and put a line through it so we'll say that I haven't but I got very close. Everything else was right.
Again say 13  17 (running total 56  64)
I also did the first part of the graph sketching question and worked out the stationary points. I did the b > a+2 (I think it was something like that) one where there were 3 alternating 'humps' but did not find the stationary points  it was correctly drawn. I didn't get onto the b = a + 2
Probably 5  7 for part one; say 5 for second part (running total 66  76)
Got through the very first part of 8 (blah  2 > 0) and a tiny bit of the next part.
Not very much say 2  3 (running total 68  79)
Where do you think this lands me, roughly? I know this is a lot to ask so if you don't feel like putting the effort into this (perfectly understandable ) then just don't reply I feel like I'm on the wrong side of the 1/2 boundary but thought I'd get someone else's opinion.
Thanks!
STEP II 2012 discussion thread
Announcements  Posted on  

AQA GCSE physics P1 unofficial mark scheme  05052016 


I have a few questions regarding question marking, although I don't need to get a grade 1 I am curious as to what mark I got.
On question one, I have very clumsily found the general term of (1x^6)^2 to be ((n+1)/n)x^6n, but then I've got the correct general term for the two other expansions, and I've got the correct formulae for the coefficient of x^n (except I've used n+1/n instead of just n+1). This yielded the wrong coefficient of x^24, and then on part (ii) I used a similar method but I didn't get 55. I then didn't attempt the remaining parts.
On Q3 I did all integrals except the last one and I nearly got it in the form f(x+root(x^2+1)), I didn't try to split it into two functions.
For question 4 I did parts (i) and (iii) correctly but I didn't get anywhere with (ii).
On 5 I did (i) correctly, and in (ii) I sketched both graphs correctly but without correct calculation of the stationary points.
On 6 I showed the expression for 16Q^2, then on question 9 I showed the first two inequalities. 
I've estimated my score to be around 7585, but it would be great to get some opinions I did:
Q1: Completed bar the x^66 coefficient I miss calculated to be 630 instead of the correct 650
Q2: Up to equating coefficients on ii) where I found my equations to be inconsistent, so I stopped
Q3: Completed
Q4: Completed bar the part in ii) where you have to consider (1/y) to show the required result
Q5: The first part fully but none of ii)
Q9: I got the first and second result fine, but I think with the second I was technically incorrect with my signs in the working 
(Original post by desijut)
I posted this is in the STEP thread, i thought i'd post it here: Also, can anyone post a solution for Q1 and Q13?

(Original post by B Jack)
I've estimated my score to be around 7585, but it would be great to get some opinions I did:
Q1: Completed bar the x^66 coefficient I miss calculated to be 630 instead of the correct 650
Q2: Up to equating coefficients on ii) where I found my equations to be inconsistent, so I stopped
Q3: Completed
Q4: Completed bar the part in ii) where you have to consider (1/y) to show the required result
Q5: The first part fully but none of ii)
Q9: I got the first and second result fine, but I think with the second I was technically incorrect with my signs in the working
Sounds like it went pretty well, good luck for III. 
Question 5 done

I found a quick way of doing Q1 (without some details). Basically, for the first part, you need to find coefficients in the expansion of (1x^6)^2 (1x^3)^1, so why not rewrite this as (1+x^3) (1x^6)^3 using difference of two squares? This gets only one infinite product, simplifying the algebra.
Likewise, for the next part, rewrite (1x^6)^2 (1x^3)^1 (1x)^1 as (1x^6)^4 P(x), where P(x) is (1+x+x^2+2x^3+2x^4+2x^5+x^6+x^7+ x^8).
Expanding the binomial is easy enough, and then it's a simple matter to extract the required coefficients at your leisure. Note that to work out coefft(x^66) I only needed to add (13 choose 3) and (14 choose 3), which is easy enough if you keep them split into prime factors. 
(Original post by mikelbird)
Question 5 done
b>a+2.  (a+b)/2 i.e. midpoint as to be expected by symmetry; (a+b) +/ root((ba)^2+4) all over 2. Symmetric about midpoint.
b = a+2  (a+1) +/ root (2). Symmetric about midpoint as expected.
These agree with your calculated answers. 
(Original post by mikelbird)
I agree with your results..and just for completeness sake.... 
Guys, I was wondering if you could give me some tips about taking step? Like how to start preparing for it? I will hopefully be taking it next year.

(Original post by Mr Dependable xD)
Guys, I was wondering if you could give me some tips about taking step? Like how to start preparing for it? I will hopefully be taking it next year.
http://www.thestudentroom.co.uk/show....php?t=1310974
http://www.thestudentroom.co.uk/show....php?t=1886802 
(Original post by GreenLantern1)
I would say it was slightly easier personally. Though a lot of people seem to have struggled and I owuld imagine these are the ones that are restricting themselves to the pure questions! 
(Original post by Flibberdyjib)
I found a quick way of doing Q1 (without some details). Basically, for the first part, you need to find coefficients in the expansion of (1x^6)^2 (1x^3)^1, so why not rewrite this as (1+x^3) (1x^6)^3 using difference of two squares? This gets only one infinite product, simplifying the algebra.
Likewise, for the next part, rewrite (1x^6)^2 (1x^3)^1 (1x)^1 as (1x^6)^4 P(x), where P(x) is (1+x+x^2+2x^3+2x^4+2x^5+x^6+x^7+ x^8).
Expanding the binomial is easy enough, and then it's a simple matter to extract the required coefficients at your leisure. Note that to work out coefft(x^66) I only needed to add (13 choose 3) and (14 choose 3), which is easy enough if you keep them split into prime factors. 
(Original post by TheMagicMan)
I think there are a couple of people who have said it was slightly on the easy side but most seem to have found it quite hard 
I'd consider myself an applied guy but, regardless, I thought this was a hard paper.

(Original post by bensmith)
I'd consider myself an applied guy but, regardless, I thought this was a hard paper.
The other pure questions seemed just to be grinding through  not easy to get out in half an hour without a mistake in the algebra somewhere. 
(Original post by msmith2512)
Agreed. I'm an applied guy too  Q9, Q11 were OK but Q10 took some slogging through. Q6 and Q8 did come out OK but from a first glance I didn't think it was exactly obvious how to solve them  with most questions I can 'see' the route to the end on just reading through.
The other pure questions seemed just to be grinding through  not easy to get out in half an hour without a mistake in the algebra somewhere. 
(Original post by msmith2512)
Agreed. I'm an applied guy too  Q9, Q11 were OK but Q10 took some slogging through. Q6 and Q8 did come out OK but from a first glance I didn't think it was exactly obvious how to solve them  with most questions I can 'see' the route to the end on just reading through.
The other pure questions seemed just to be grinding through  not easy to get out in half an hour without a mistake in the algebra somewhere.
Q9, 11 and 13 were friendly targets IMO; I thought the applied was pretty generous, to be fair.
(Original post by TheMagicMan)
3 and 4 really weren't a grind at all...less than a page of A4 to solve each 
(Original post by TheMagicMan)
3 and 4 really weren't a grind at all...less than a page of A4 to solve each 
(Original post by TheMagicMan)
This is a nice solution but not something I would ever have come up with in the exam..If I can bang something out I usually just go with the 'brute force' method . Question 7 too has an elegant approach which I would never have looked for in an exam
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