[Wahrheit]

(Original post by Gibbers)
God I did so badly on that paper... bad enough that I have probably wrecked my chances of meeting my 3 A's offer. Damn. I think only low grade boundaries can save me - in addition to doing absurdly well in my C1 and C2 retakes... Did other people find this paper hard?

Also, if you could Mr M, can you explain how you got 1(ii)?? I got an answer like 3x-9 or something =(, and for 9(i), I got ln2000 - 3/2 and I have no idea where I went wrong to end up with b=2000.

All I can now is hope.

for 1 (ii) the second to last stage is 3x-9/(x-1)(x-3)(x-4) then you can write that as 3(x-3)/(x-1)(x-3)(x-4) and then cancel the (x-3) terms, so by the sounds of it you were just 1 line of working away from the answer.

[Antonton]

(Original post by Mr M)
You are welcome. I'm off home now but will be able to answer questions in about 45 mins so anyone can post here and I will deal with them in a bit.

I forgot whether or not I put Pi/4 -2/3 or + 2/3 for question 7, so if I get it wrong will I get the 6 marks for correct intergration and methods?

For question 9ii) if you intergrated your part 9i) how many marks would you get? You wouldnt lose all your marks surely for intergration whatever you got as A B or C ?

[Doctor.]

(Original post by Tateco)
I did exactly the same. The consensus is that we would lose 3 marks, maybe 2 if we're lucky.

I think you will get 1 mark for starting to do it as by parts, another mark for laying it out right but then lose the last three for integrating x/(x+2) wrong.

AH fair enough, 2 marks out of 5 isn't bad. I was just so stressing out - Ended up panicking and just rushed it

I'm sure you've done fine me on the other hand...not so fine :/

[Antonton]

What does everyone think it will be for a grade A* A B C D E? What is everyone's overall opinion on the paper?

[Tateco]

(Original post by Doctor.)
AH fair enough, 2 marks out of 5 isn't bad. I was just so stressing out - Ended up panicking and just rushed it

I'm sure you've done fine me on the other hand...not so fine :/

I honestly think that it was a very hard paper though, with some very odd things that you would only know how to do if you were really prepared, hoping for low grade boundaries.

[Doctor.]

(Original post by Tateco)
I honestly think that it was a very hard paper though, with some very odd things that you would only know how to do if you were really prepared, hoping for low grade boundaries.

So true, I found the vector questions more complicated than normal OCR are just trying to screw us all over - just like AQA :/

[Starlight94]

Oh my god kill me now, I've done terrible. :/

[Sweetcorn_1]

(Original post by Mr M)
Mr M's OCR (not OCR MEI) Core 4 answers June 2012


1.
(ii) (4 marks)
I did the initial bit right by removing the (x-3) but then I did something (idk what) and got it wrong.


3.
(ii) (1 mark)

I used -1/4<x<1/4

4. (6 marks)

I left it as e^2y=ln|secx| + whatever, didn't want to ln a ln.

5.
(ii) (3 marks)
I know I got 0 for this.


9 (i) (5 marks)

I dunno why but I messed this up, I did get one of the numbers right though.

(ii) (4 marks)

Integrated my wrong answer.

10
(iii) 3 : 2 (3 marks)

got /45=/44 or something (/=root)

Was my last exam and I need an A in this

Do you think I can get it?

[bobfarrow]

for question 4 differentiated -tan(x) for some stupid reason and followed through with -sec^2(x). How many marks would i get for this?

[Gibbers]

(Original post by Antonton)
What does everyone think it will be for a grade A* A B C D E? What is everyone's overall opinion on the paper?

Well in my opinion, and a lot of my friends, it was a difficult paper - last year, the grade boundaries were:

A=51
B=45
C=39
D=33

I think the year before last it was A=54 and B=48, but I personally think that this paper was on the lower end, 51/52 for an A and 45/46 for a B. But then again, that might just be wishful thinking because I did so badly. It might be that people found it challenging but ultimately did very good in the paper; which would be bad for people like me who found it challenging and didn't do very well.

Honestly in all the past papers I did as preparation, I was getting mid and low 60's, I think from looking at these answers and guessing marks I would gain for working that I probably just scraped a 45 in this paper.

[a10]

HOW DO YOU GET T=1 AND T=1/3

X= 2T^2 -1 Y= T^3 + T

so parrallel to y axis so x = 0?

2t^2 -1 = 0

2t^2 =1

t^2 = 1/2

t= sqrt 1/2 = root 2/2(rationalised)

thats what i got then i subbed in the value into the y equation to get y?

hw many marks would i lose but honestly someone explain hw they get t =1 and t=1/3 please

[Sem193]

(Original post by Tateco)
I honestly think that it was a very hard paper though, with some very odd things that you would only know how to do if you were really prepared, hoping for low grade boundaries.

I hope the grade boundaries are low too! It was kind of a strange paper. What do you think will be the grade boundaries for an A and B?

[jamieward]

how did u show 9 part 1), that OA was on the line l1?

[ila4e123]

Mr M

1) for Q2 my answer was xln|x+2|-x+2ln|x+2|+c, is this right?
2) for Q4, the differential equation, how many marks will i get up to the part where i got 0.5e^2y=-ln|secx| + 0.5, i then lost it from here.
3) for Q8bi) or ii) is there any marks available for differentiating the parametric to get (3t^2+1)/4t
4) for 10iii) do i get follow through marks if i made up the pt of intersection and then solve to get the ratio.

Many Thanks

(Original post by Mr M)
Mr M's OCR (not OCR MEI) Core 4 answers June 2012


1. (i) (2 marks)

(ii) (4 marks)


2. (5 marks)


3. (i) (6 marks)

(ii) (1 mark)


4. (6 marks)


5. (i) 60 degrees (2 marks)

(ii) (3 marks)


6. Show integration by substitution (7 marks)


7. (7 marks)


8. (a) -1 (4 marks)

(b) (i) (-1, 0) (3 marks)

(ii) or (3 marks)


9 (i) (5 marks)

(ii) (4 marks)


10 (i) Show (3 marks)

(ii) Show (4 marks)

(iii) 3 : 2 (3 marks)

[Mattdavidcool]

$ latex x^2 $

[Sem193]

(Original post by a10)
HOW DO YOU GET T=1 AND T=1/3

X= 2T^2 -1 Y= T^3 + T

so parrallel to y axis so x = 0?

2t^2 -1 = 0

2t^2 =1

t^2 = 1/2

t= sqrt 1/2 = root 2/2(rationalised)

thats what i got then i subbed in the value into the y equation to get y?

hw many marks would i lose but honestly someone explain hw they get t =1 and t=1/3 please

The way I did it was I made dy/dt=dx/dt and then found it like that. So I made 3t^2+1=4t and then wrote 3t^2-4t+1 and solved quadratic.

[chja]

(Original post by antonton)
what does everyone think it will be for a grade a* a b c d e? What is everyone's overall opinion on the paper?

a*=60 a=54 b=49 c=44 d=39 e=35

[Mr M]

(Original post by Doctor.)
Mr M,

I got


For question 4, would that be acceptable?

EDIT: Just read what you wrote Mr M, We'll we waiting!

Absolutely fine.

[Tateco]

(Original post by Sem193)
I hope the grade boundaries are low too! It was kind of a strange paper. What do you think will be the grade boundaries for an A and B?

No idea, I'm biased because I found it hard.

I'm hoping it will be mid 50s or less for an A, considering recently the boundaries have been 51, 54, 55 and 62

[Emissionspectra]

:O I think I've dropped a max of 4 marks