OCR C2 Exam May 18th 2012

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are there any past papers you would say were on the same level of difficulty as this one?

So we can find approximate grade boundaries.

this was similar to june 2011 and jan 2012 so it will be 58/72 for an A around 57- 59

Is this mEI?

Original post by J DOT A

Think I have just dropped 3 marks... depends on if I get method marks for that damn obtuse one (no idea).

radius= 15/sqrt pi
x=2/3
1/2<y<2
x=4/3
integration was 69.999
C intercept was -4
cos alpha was 5/sqrt 29
LINE OF trapezia was UNDER the curve, underestimate

i got all those except the radius was sq root of 225 if i remember so just 15 the pi's cancelled out

Reply 323

J DOT A

Also area of segment was like 10.9 or something?

Reply 324

abarlas123

did anyone get 15 for the radius

Reply 325

issyconnor

Original post by erniiee

I agree.

I got this as well, then realised my calculator wasn't in radians mode!

You might find it helpful, when you do core three or four, to bring 2 calculators in the exam. One in degree mode, one in radian mode. To distinguish between the two just put a sticky label at the time with 'degree' on the calculator in degree mode. It seems like a stupid idea, but my teacher recommended it as one of my worries about core 2 was getting the trig questions wrong because I'm quite forgetful and would not remember to change from degree to radian.

:smile:

Reply 326

issyconnor

Original post by abarlas123

did anyone get 15 for the radius

Yes. That was right.

Reply 327

J DOT A

Original post by a10

i got all those except the radius was sq root of 225 if i remember so just 15 the pi's cancelled out

no its sqrt of 225/pi which is 15/pi
The pi's dont cancel? I typed 15/pi in and know that is correct as i got 45 as the area of sector.

Reply 328

J DOT A

Original post by issyconnor

Yes. That was right.

How is 15 correct? it's 15/sqrt pi

Reply 329

dongonaeatu

Is this ocr mei or just ocr?

Reply 330

tahseen1995

Original post by OJC

Is this mEI?

Nope just OCR

Reply 331

samjj8

Original post by a10

Ouch dude unlucky this was a really nice paper, sum of the marks were give aways so easy xD how many past papers had you done?!

It wasn't a nice paper. It was an OK paper.

Question 7 part 2 wasn't nice.
Question 9 wasn't nice.

9 wasn't impossible, but it was a head scratching question.

Reply 332

J DOT A

What did everyone get for the radius question and area of segment

Reply 333

ingeek2010

The radius is definitely 15cm.

If you substitute into A= 1/2R^2THETA.

you get A= 0.5 * 15^2 * (2/5)Pi
A = 45Pi

It was 15 and the area of segment was 34.4

:smile:

Reply 334

AKayaker

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
Will i get the marks for this method, also will I lose marks as I think i forgot to change both down to surds (I left them as sqrt(25/29) and -sqrt(40/49) not 5sqrt29/29 and -2sqrt(10)/7

Reply 335

om-nom ._.

Original post by OJC

Is this mEI?

no ocr

Reply 336

cameron95

What did people get for question 4 -
4cos^2(x) - sin(x) - 7 = 0. (or something like that)

i got sinx=-3/4 and -1, but I think they were meant to be positve. I don't know what i did wrong as i went through the question twice as i thought they were wrong.

Reply 337

issyconnor

Original post by J DOT A

How is 15 correct? it's 15/sqrt pi

From what I can remember the area they gave for the sector was 45pi. I got the angle as 2pi over 5. If you use the area formula 0.5*r²*angle you get 225. If you square root that you get 15.

I may be wrong though. TBH I'm just trying to forget about C" and am concentrating now on M1, C3 and C4.