OCR FP1 (Non-MEI) 14th May 2015

Yeh i thought there was at first, because there was 2 positions of the plus and minus signs,
but when you did all 4, 2 of them just converted into the opposite ones so it just came out with 2 of the same answers.




This is what i had for the point of intersection. Did anyone get the same?

Okay awesome thanks pal,
that was the question i was wary about. I didnt originally put -2 until the last minute, i took it from the circles centre haha,

Hope you and everyone has done great, bring on core 2 haha

hahaha I actually managed to get the hard answers like 29, but for the loci bit I got the right point but I gave it as coordinates 😂😂😂 anyway did anybody get 1.25 for the summations one?

Yeah we all did - that was a nice question - I especially liked how there were three terms and the whole thing quite literally lived up to the expectation of it being a "telescope" method

Any grade boundary predictions?

I have a feeling the A boundary might be 60-63 ish. Just guessing though!

I got -(root3) + i

your circle was also 2 negative x units from the origin!

29

you got $(a^2 + b^2 + y^2)^2)$ which was 64
then took away $2(a^2b^2 + a^2y^2 + b^2y^2)$ which was 32

$64-32[br]$
then refer to the original equation of x
$aby = -d/a = -3[br]32-3=29$

you couldn't use your equation in u to find aby because you had no way of deciding whether root 9 was -3 or +3, so refer to the original equation

-d/a = -3/1 = -3

32-3=29

I did it right for 10 ii but had a carry on error from 10 i, and I didn't put much working. Do you need to show working if you get the right answer? Would I get all the marks for working?