Arsey's C3 Edexcel Summer 2013 Model Solutions (UK replaced paper)Watch
files at the bottom of the post
I had added my solutions to all 3 papers; UK replaced (the one most of you did), UK original and Non-UK paper.
The Non-UK paper was by far the easiest. Easier than a standard C3 paper.
The UK original paper certainly wasn't easy, it was harder than a standard paper but there really wasn't anything that unusual, pretty much a similar question had been asked before (except maybe the tan question)
The UK replaced paper was by far the most difficult. I still maintain it wasn't as outrageously difficult as many think. I think in a few years students will think it is a hard paper but will not be able to understand all the fuss it created.
EDIT - BOUNDARIES
I have absolutely no idea about the boundaries but my money would be on around 50-52 for an A; 56 -59 for 90 and 62 - 66 for 100ums
This was a very tricky paper. I appreciate there are a lot of upset and angry feelings floating around. However, I have read an awful lot of misinformed and inaccurate comments on social media sites. You can take or leave the following comments but they are my opinions.
There was nothing on this paper that isn't on current specification. Some questions required skills that are considered pre-requisite knowledge from Core 1/2 and GCSE Mathematics. Knowledge of GCSE topics such as Ratio, Similar triangles, bounds, basic trigonometry facts is expected knowledge and does not need to be listed on the specification for Core 3.
The final question isn't a Mechanics question. I would agree that the context of the question was in a Mechanics style but it was irrelevant as to what needed to be done to answer the question. The whole context was completely pointless.
The fact that it appears that a few centres have taken the original paper is really irrelevant to those who took the replaced paper. Their results will have no impact what-so-ever on the grade boundaries for the replaced paper. Also, it really isn't Edexcel's fault that some centres made this error. I personally read the instructions that they sent out weeks ago, so really some examination officers need to be made accountable for their error.
I have read comments saying that their teachers couldn't even do the paper, or that teachers took 3 hours to do it. I am sorry but a teacher should not be teaching students A-Level Mathematics if they could not answer every question correctly (barring silly errors) within the time. I completed the paper within 40min. That said, I did originally miss the second solution to the final functions question, but that was rather sneaky.
This paper was not written at the last minute, it is very likely it was written at the same time as the original paper by the same examiner and would have probably been used next year. That said, Edexcel state that they aim for their papers to be of comparable difficulty and alter the grade boundaries accounts for slight differences. I am very interested to see the original paper, I would be staggered if it is anywhere near as hard. I do think Edexcel need to work much harder to ensure that their papers are of comparable difficulty. There has been quite a significant difference in the difficulty of some of the UK and non-UK papers. Had UK candidates took the international M2 paper, I do think there would have been a huge number of complaints.
The best piece of advice I can give is to try to put it out of your mind; the grade boundaries will be really low and hopefully this means that the Core 4 paper will be a lot nicer. Put your energy into smashing Core 4.
Q1. Reasonable algebraic division. Similar has been asked before.
Q2. Straight forward sketching and transforming graphs. Harder questions have been asked before.'
Q3. Okay part (a) is pretty hard. The first step is reasonable obvious and you really should know that sin x = cos (90 - x) as it is a pretty basic trig fact taught at GCSE and in Core 2. That said part (a) will be an epic bloodbath.
Part b) was fairly easy; similar and harder questions have been asked.
(at most this qu ought to be 3 marks lost)
Q4. Part a) is fairly straight forward. Very standard. Part b) was a little tricky and part c) is on almost every single paper, gift marks.
Q5. a) and b) are pretty reasonable c) is pretty hard.
Q6. a) isn't any harder than a C2 logs question (although, I have just noticed 5 is outside the data range!)
b) is hard but a very similar question was asked on one of the recent papers.
Q7. a) and c) are very easy. Similar questions have been asked to part b) on recent papers. I appreciate that the fact 5 wasn't marked would have caused confusion. However, now you know it is 5 you ought to accept that it really isn't that hard to see why.
d) is very hard and the second solution is rather sneaky.
Q8. If you ignore the pointless confusing context, this question isn't too bad, certainly harder than normal mind. It was very sneaky that they swapped Sin and Cos around originally but I warn my students to always check for this. It is why I always write out the complete expression for the addition rule to compare.
Understanding that you need to put the max value on the bottom to get the min V is GCSE bounds and the exact same thing was on the Jan 13 paper.
c) and d) are quite confusing but really not that difficult.
It is fairly obvious given the reaction to the paper that the average mark is going to be very low. The lowest ever boundary for an A on the current spec papers was 46/75 for an A and 60/75 for 100ums. I wouldn't be surprised if this was another sub 50 for an A paper.
At the other end it has been as low as 21/75 for an E. 25 should be enough for an E on this paper, there were 25 reasonably straightforward marks.
I will sort out some solutions to the international paper tomorrow if I have time.
I am not going to be around for very long, I am pretty tired. So don't get too stressed if I don't answer your questions tonight or miss them in what I expect to be a big thread.
Remember, no one knows what the boundaries will be.
I cannot tell you how many marks would this be worth etc a lot of the time because most of the awkward questions will depend on the MS
There really are not as many commonly called ecf marks as you would think. You cannot think 1 error means 1 mark lost, it is rarely that simple.
Finally if you are taking C4, take the time to read through some of my past C4 threads, pre-exam, post exam. There will be some good tips you pick up and you can learn from the errors others made.
edit: damn i had a good start but completely messed up the last two questions
did part b of the log question without a problem screwed up part a..
I hate Edexcel.
Edit: You have included two solutions to part 6(a). The questions says -1<x<2 so the only solution would be x=7/5 not x=5.
edit: in the first question I didn't read it properly and I thought e was ACTUALLY e, the number hahahah!
x=5 is invalid as it does not lie in the range given
Thankfully I wasn't relying on c3 to bring my overall grade to an A, but this ain't even funny.
Edexcel try coming up with the slogan, 'changing lives' and yet what they've done, is potentially ruined the chances of people getting into uni.
Ditto the answers (other than 6a as x cant be 5)
- Study Helper
Edit: Clearly some people are jealous that I wasn't caught out as much as they were, what a shame