Mr M's OCR Core 1 (not OCR MEI) May 2016 Answers

https://gyazo.com/1fc8fc02d2bdbc6d4a0ec7b798c25e09 I am pretty sure Mr M is right

Mr M's OCR (not OCR MEI) Core 1 May 2016 Answers


1. (i) $2x^2-9$ (2 marks)

(ii) -10 (2 marks)


2. $-\frac{1}{4}+\frac{3\sqrt5}{4}$ (4 marks)


3. $x = -3$ and $y = -5$ or $x = \frac{3}{5}$ and $y = \frac{29}{5}$ (5 marks)


4. $y=\frac{1}{16}$ or $y=81$ (5 marks)


5. (i) $2^{-6}$ (2 marks)

(ii) $2^{\frac{13}{3}}$ (3 marks)


6. (i) $-2(x-3)^2 + 22$ (4 marks)

(ii) (3, 22) (2 marks)


7. (i) Negative cubic with the x axis as a tangent at (0, 0) and crossing the x axis at (3, 0) (3 marks)

(ii) $y=(x-2)^2(5-x)$ (2 marks)

(iii) Stretch parallel to the y axis scale factor 0.5 (2 marks)


8. (i) Show ... (3 marks)

(ii) The gradient at A is 20 and as h approaches 0 the gradient of the line also becomes 20 (1 mark)

(iii) $\frac{201}{4}$ (3 marks)


9. $k<-2$ or $k>5$ (7 marks)


10. (i) Centre (4, 3) Radius $3\sqrt{5}$ (3 marks)

(ii) $y=2x-20$ (6 marks)

(iii) $y=2x+10$ (3 marks)

(iv) $0<r<3\sqrt{5}-5$ (2 marks)


11. $a=27$ (8 marks)


This was definitely the most difficult Core 1 ever. I'll be around to discuss questions later for a bit. Post in the thread, don't private message me as the system is running very slow.

For the simultaneous equation, should it be x=3, y=5, and x=-3/5 and y=-29/5
I thought the simultaneous equations were x^2 + y^2 = 34
and 3x-y-4=0

Hey Mr M,

I drew the graph as a positive graph instead of negative but it passed through the correct points. How many marks do you think I would have lost?

thank you sir for the answers. For part 8i i think i did the wrong method to 'show that' however i still got the answer they were looking for. Will i drop marks on this?

thank you sir for the answers. For part 8i i think i did the wrong method to 'show that' however i still got the answer they were looking for. Will i drop marks on this?

Do you have any predictions for grade boundaries? Thank you

For the simultaneous equation, should it be x=3, y=5, and x=-3/5 and y=-29/5

If for the last question i differentiaited a/x as just -a and continued the rest of the question and got an answer. How many marks out of the 8 can i expect ?

Hey, I was wondering if you'll be posting a mark scheme for OCR MEI?
Thank you

how many marks for question 10ii and 10iii can i expect if i found the wrong gradient for the line from the centre of the circle to the point (-1/3) and then did the rest of the question right, and also used the gradient 3 for the next question? will I lose all the marks or still pick up method marks? If i will pick up method marks, out of the 9 for these two questions how many do you think I would get? Thank you

This is annoying but I drew the graph question wrong - I got a negative cubic with roots (0,0) and (-3,0) instead of (3,0)

How many marks would that be out of 3?

No the solutions provided are correct.