FP1 OCR Post Exam Discussion 11/06/2010

Also for question 4, did the argument have to be in radians?

Thanks Mr M

Two things: 1) What do you think the grade boundaries would be
2) Have you got the answers for Core 4?

Thanks again

no i think they would accept degrees in you marked it with a degree symbol

1) dunno - it didn't seem particularly difficult so not high
2) i posted them some time ago in the C4 thread

no i think they would accept degrees in you marked it with a degree symbol

What a stupid question! Of course I was listening.... just, forgot it, that's all

If you have a copy of the FP1 paper, could you tell me what the original quadratic equation was on Question 7? - The one about roots

Thanks! Also, for question 2 (ii) I didn't fully factorise my answer and left it as 1/3 n (4n^2 - 1). Do you think I've only dropped one mark there?

yes

x^2 +2kx +k = 0

mr m i made one error after factorising the summations equation then whilst expanding the other brackets i made a silly mistake so my answer is wrong but up until then my method was right and i took 1/3 out. how many marks do u think i would lose?

OCR (not OCR MEI) FP1 Answers June 2010



9 (i) $a(a-1)$ (3 marks)

(ii) (a) Inconsistent

(b) Consistent but no unique solution

(c) Consistent with unique solution

If i ended up with k(x^2) - 4(k^2)x + 4(k^2) = 0
Will I still get any marks, as it is still the correct answer, but I just didn't divide throughout by k?

I wrote B as inconsistent, how many marks do you think I would lose for that? Also, how do you actually show that it was consistent?

Thankyou so much, you're awesome.

Thanks a lot that is great! Two things:

For the shaded regeion where were we supposed to shade? I shaded inside the circle, between Re(z)=3 and Re(z)=6. Wasn't too sure on that!

And for the one marker on whether it converges, do you think I would get the mark for just saying that as n increases the result can get infinitely big/there is no limit on it's value?

Cheers!

Sorry didn't see this.

Shade right side of the line and the interior of the circle.

(ii) 2 x 2 matrix top row -7 - 20 bottom row 11 -20 (4 marks)

(ii) Shade region (2 marks)

Sorry didn't see this.

Shade right side of the line and the interior of the circle.

Monsieur M,
How many marks would I lose for the following errors:

1) Forgetting the minus sign in front of 7 in 2 part ii in the matrices question

2) 6 part ii, I only shaded in the fourth quadrant when I had to shade part of the first quadrant to the right of x=3

3) Question 7 I but x^2 + 4kx +4k (didn't put -4kx)

Merci Mr. M... I've told you this before, but once more won't hurt, you are a legend