Mr M's OCR (not OCR MEI) Core 2 Answers May 2015

How difficult did you think it was compared to last year?

thank you so much Mr M. think i got full marks... abiding by the fact my method marks were suffice.. just one question:
for the N=24 question, i had derived 24 from a quadratic equation i factorised... however i factorised the equation using my calculator.. would that drop me any marks?

Hello Mr M

for question 6 I wrote x = 2 , 3 and -5 instead of the answer you gave.
How many marks would I lose?

Hi

Question 1iii) i wrote correct working, but typed wrongly into calculator producing a positive number similar to the answer - would i lose both marks

question 8 (a) i produced the correct working but again typed it wrong into my calculator, i got 27.1 - how many would be lost

question 9 (b) iiii i got one of the solutions 3.32 but not the other one - how many would be lost

Yes I expect so.

Mr M's OCR (not OCR MEI) Core 2 Answers May 2015


1. (i) -2 (1 mark)

(ii) 3072 (2 marks)

(iii) -1048575 (2 marks)


2. (i) 21.4 (4 marks)

(ii) Increase the number of strips (1 mark)


3. (i) 32.1 (4 marks)

(ii) 22.7 (5 marks)


4. (i) $64+192ax+240a^2x^2$ (4 marks)

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


5. $y=4x^{\frac{3}{2}}-7x-3$ (7 marks)


6. (i) $f(x)=(x-2)(x-3)(x+5)$ (4 marks)

(ii) 256 (4 marks)

(iii) The graph has positive and negative y values across this interval (2 marks)


7. (i) 62 (2 marks)

(ii) Show (3 marks)

(iii) 24 (6 marks)


8. (a) 17.1 (4 marks)

(b) x = 32 and y = 8 (5 marks)


9. (i) (a) $6 \pi - \alpha$ (1 mark)

(b) $3 \pi - \alpha$ (2 marks)

(ii) Draw one period of the sine graph with half the amplitude of the cosine graph (2 marks)

(iiii) 3.32 and 12.7 (4 marks)

Thanks so much Mr M. The only issue I have is the two questions on 9. that are 6pi - a and the two marker. I answered in degrees instead of radians, which is annoying. How many marks out of three will I get for that? Thanks!

You'll just drop a single mark for working in degrees. Read the question more carefully in future!

1iii) lose 1

8a) lose 1 or more

9biii) lose 1

This is the first time I've mustered up the courage to look at the mark scheme after that nightmare of an exam.

For the very last part of question 9 I got it to tanx = 2 and then instead of time sing by 3 I devided by 3. How many marks do you think I will get out of 4. Also do they do ECF on these papers. I got the first part of 9 wrong and the second part as I didn't realise it had been stretched, my answer to the second part would have been correct had I realised so had both my answers been scaled up I would have got the answers. Will any get any marks of the 3 for the 2 questions? Thanks. Sorry for asking a question on a dead thread and thanks for the mark scheme ( TSR should pay you for all thee help you give).