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AQA A2 Mathematics Pure Core 4 MPC4 - 17th June 2016

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I think full ums would be like 64-67 or something like that; and I'm hoping I got A* overall so I don't have to resit C3 overall to get the A*.Bear in mind people on twitter etc found C4 hard aswell post the vectors question.

Thanks that's made me quite a bit more confident as I didn't get the last vector question but after that point I just lost marks on relying on my arithmetic instead of my calc for the parametric question (i got e^4 because I put 3/2-3/4(e^2)= 3/2(e^2)) but strangely I think I've done much better on Core 3

Reply 901

Cal 1

Excuse the disgusting looking dy/dx fraction I couldn't be bothered to rearrange. Would I drop marks for leaving the dy/dx in terms of t as I did?

Reply 902

Parhomus

Original post by Cal 1

Excuse the disgusting looking dy/dx fraction I couldn't be bothered to rearrange. Would I drop marks for leaving the dy/dx in terms of t as I did?

That's what you're supposed to do ;P

Reply 903

Brad100498

Hey

I thought C4 was pretty good. However, I think I may have got a different answer for Question 4c: it wanted the integral in the form p + q ln[3] and I got p as -57/2 or something like, not -69/2 but I'm sure I checked it on my graphing calculator and it was correct but assume it's wrong. Also, for Question 6c, I got negative versions of lambda for points C and D. Assuming that's incorrect, and I made a sign error in my working, how many marks will have I lost from these two errors would you say? Thank you :smile:

Reply 904

Cal 1

Original post by Parhomus

That's what you're supposed to do ;P

I mean leaving the dy/dx in that unsimplified form (where there's a fraction over another fraction)?

Reply 905

Parhomus

Original post by Cal 1

I mean leaving the dy/dx in that unsimplified form (where there's a fraction over another fraction)?

Oh; I didn't bother doing that either; when I just got the expressions for dx/dt and dy/dt and wrote an expression for dy/dx , I then just plugged in the value of t instead of simplifying then doing it; so i think it's fine.

Reply 906

gcsekid

Original post by Cal 1

Excuse the disgusting looking dy/dx fraction I couldn't be bothered to rearrange. Would I drop marks for leaving the dy/dx in terms of t as I did?

Your handwriting is quality

Reply 907

gcsekid

I showed that the vectors intersect but never showed the coordinates
Also in the diff equation i seperated the variables but then got 54ysin3y as I multiplied to get 6/4+9x then carried out integration by parts
How many marks would I lose? Btw i never got pi as constant

(edited 7 years ago)

Reply 908

Parhomus

Original post by gcsekid

The thing is; that if when you plug x=0 and y=Pi/3 and it works out then it should be correct. There isn't only one form which it can be in; there will obviously be a main one which it would be in, but if I remember correctly from what one of my classmates did in the mock we did; they have multiple different solutions for diff questions.So you may have got the marks assuming you've done the rest correct.

Reply 909

asdfaeth

how many marks was the last question?

Posted from TSR Mobile

Reply 910

Mowerharvey

Original post by asdfaeth

how many marks was the last question?

Posted from TSR Mobile

Part a) was 3 marks and part b) was 7 marks. 10 marks overall.

Reply 911

A12R34

Original post by Mowerharvey

Part a) was 3 marks and part b) was 7 marks. 10 marks overall.

What was the 7 mark part?

I think i forgot a negative sign in my dx/dt so i got -1/2e^4, but I can't remember if we needed that in the next question?

Reply 912

Mowerharvey

Original post by A12R34

What was the 7 mark part?

I think i forgot a negative sign in my dx/dt so i got -1/2e^4, but I can't remember if we needed that in the next question?

I think you're thinking of the penultimate question, the one with the parametric equations? The last question was with the differential equation.

Reply 913

DEWR98

I've just realised how to do the Vectors question, which is so frustrating because I crossed out the right method in the exam (thinking it'd be long winded and wouldn't get me anywhere). Does this ever happen to anyone after an exam frequently( the realisation)?

Reply 914

C0balt

Original post by DEWR98

Yeah it does. I've learnt to not cross out the working until I finish doing the right method and I'm absolutely sure that it's right though.

Reply 915

Rabadon

Original post by DEWR98

what was the correct way??

Reply 916

mertyuiop

Original post by Rabadon

what was the correct way??

I've many different methods of doing it but i did it by using that AB was three times as big as CD so AB was 4root35 i think and CD was 4root35/3. Then i realised the intersection (i called it P) was the midpoint so i worked out a vector equation for CP (was something like 3-3y, -5+5y, -1+y but i dont remember exactly). Then i worked out the modulus of that which gave you a quadratic which i set equal to (4root35/6)^2 and then solved it giving me 1/3 and 5/3☺ hope that makes sense☺

(edited 7 years ago)

Reply 917

Chickychick

What would 40/45 marks be in C4 because right now I am panicking :frown:

Reply 918

Qcomber

Original post by Chickychick

What would 40/45 marks be in C4 because right now I am panicking :frown:

Probably a low C

Reply 919

DEWR98

Original post by Rabadon

what was the correct way??

Basically I would've worked out magnitude of AB divided it by 3 then 2 to get the magnitude from intersection point to C or D then get whatever that vector was and make a quadratic. I hope it's 59 again for 90ums like a few years ago, in case I dropped the odd few apart from my definite 10