Mr M's OCR (not OCR MEI) Core 2 Answers May 2012 <strong><font
Maths exam discussion - share revision tips in preparation for GCSE, A Level and other maths exams and discuss how they went afterwards.
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Re: Mr M's OCR (not OCR MEI) Core 2 Answers May 2012hey how much do you think will be lost for Q4, i found 2 extra values... including the ones you've given, i hope it's just one..(Original post by Mr M)
[B][U]]ks)
also for 7B, i found 3 root 3 over 8, however i put this value into Siny to get 40 degrees something, would i still get all the marks.. ?
Thanks so much for the answers btw, really appreciate it. -
Re: Mr M's OCR (not OCR MEI) Core 2 Answers May 2012the mark scheme hasn't been finalised yet so no-one knows(Original post by matty b)
what are the marks for on q's 9aii, 9bii , 8ii and 7aii? i know there's an answer mark, but what about the method marks? -
Re: Mr M's OCR (not OCR MEI) Core 2 Answers May 2012the questions are here(Original post by IShouldBeRevising_)
Hey do you remember what the last question was by any chance, I mean the last part of the last question one that was worth 5 marks.
http://www.thestudentroom.co.uk/show...003552&page=18 -
Re: Mr M's OCR (not OCR MEI) Core 2 Answers May 2012They are exact values so should be fine.(Original post by AKayaker)
Hi Mr M
For the alpha beta question there was a cheat method on the calculator
For the alpha if you did (cos(tan-1(0.4)))^2 the calculator gave you 25/29 so you could just write down the answer as sqrt(25/29)
the same thing also worked for the beta question
This method meant I had hardly any workings, will I get all the marks for the answer, also will I lose marks as I think i forgot to change both down to surds (I left them as 5/sqrt(29) and -sqrt(40)/7 ) as it didn't say in the question it had to be simplified and I stupidly forgot -
Re: Mr M's OCR (not OCR MEI) Core 2 Answers May 2012Yeah it was them thanks(Original post by jodiedoodles)
pretty sure a was log (base 2) 27, r was log (base 2) y
It was definately those two, just can't quite remember which was around! -
Re: Mr M's OCR (not OCR MEI) Core 2 Answers May 2012Q4) solve 4cos^2+7sinx-7=0, between 0 and 360(Original post by JessLamb)
why are these correct? i'm confused how you got those answers?
4(1 - (sinx)^2 ) + 7sinx - 7
= - 4sinx^2 + 7sinx - 3 = 0
4sinx^2 - 7sinx + 3 = 0
(4sinx - 3) (sinx - 1) = 0
therefore sinx = 3/4 and 1
sin^-1(3/4) = 48.6 and (180 - 48.6)
sin^-1(1) = 90
therefore, x = 48.6, 90 and 131.4 -
Re: Mr M's OCR (not OCR MEI) Core 2 Answers May 2012Lose no more than 2 marks.(Original post by jodiedoodles)
Mr M , for the last question I must have done something stupid somewhere as I worked out y = 6, and substituting this back in got -3 (we wanted 3) . I think I've just messed my signs up somewhere, but I'm pretty sure I done the same working as my friend who got the correct answer as 2/3 (I think?)
Would I still gain method marks, and lose the answer mark? How many marks do you estimate I would lose here?
Thanks! -
Re: Mr M's OCR (not OCR MEI) Core 2 Answers May 2012Mr m I did not write 15 (CM) for the radius question I just wrote 15 will I still get the marks(Original post by Mr M)
They are exact values so should be fine. -
Re: Mr M's OCR (not OCR MEI) Core 2 Answers May 2012Just lose one mark if you did your calculation correctly.(Original post by sj_1995)
If, foolishly, I did (3+2x)^5 - (3-2x)^5 instead of plus, would I get any marks? Im sure i read somewhere in an Old OCR mark scheme there was a mark for correct working put incorrect question copying!
Or am I dreaming....
Other than that really happy with the paper! -
Re: Mr M's OCR (not OCR MEI) Core 2 Answers May 2012
Hi Mr M,
For question 4, I used the right trig identities and got to 4sin^2x - 7sinx + 3 = 0 (not sure if I've remembered it correctly) but then I must've stupidly factorised it wrong and ended up with x= 30, 150.
Do you think I'd get any of the 6 marks, seeing as my method was correct(ish)?
Thankyou! -
Re: Mr M's OCR (not OCR MEI) Core 2 Answers May 2012Lose 1 mark(Original post by halii_94)
Mr M for 7ii I got positive the answer you put not negative
How many marks would I lose?
And for 5b I misread the first 9 for 19
but did the rest ok how many marks would I lose there?
Thanks
Lose only 1 mark if you are lucky -
Re: Mr M's OCR (not OCR MEI) Core 2 Answers May 2012Thanks! Sorry to be a pain but do you have any idea how many raw marks around 75-80 UMS would need?(Original post by Mr M)
Lose no more than 2 marks.
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Re: Mr M's OCR (not OCR MEI) Core 2 Answers May 2012Just lose 1 mark and then get full marks(Original post by peachesandcream77)
hey how much do you think will be lost for Q4, i found 2 extra values... including the ones you've given, i hope it's just one..
also for 7B, i found 3 root 3 over 8, however i put this value into Siny to get 40 degrees something, would i still get all the marks.. ?
Thanks so much for the answers btw, really appreciate it. -
Re: Mr M's OCR (not OCR MEI) Core 2 Answers May 2012It isn't a solution - I don't know where your 270 came from?(Original post by Ursin)
Messed up a bit, probably got somewhere in the high 50s, but could have done with high 60s really.
How come you couldn't have 270 for question 4? -
Re: Mr M's OCR (not OCR MEI) Core 2 Answers May 2012The answer is 15. That's correct.(Original post by IShouldBeRevising_)
Mr m I did not write 15 (CM) for the radius question I just wrote 15 will I still get the marks