OCR MEI FP3 - June 13th

Scroll to see replies

Hi, Would it be possible for you to scan the markov chains question? Thank you!
I wish I was allowed the paper , to take out with me :frown:

I dont't see why they dont let us take papers out!

Here it is

markov.JPG82.1KB

Reply 21

A.Majid

Original post by WKH

actually is it possible to scan the whole paper?
want to redo it again and check what have I done wrong

Thanks a lot

Arite.. Bit of advice though, there's no point, you're only just gonna beat yourself up.

This isn't all of the paper, but all of it is up in the thread.

Original post by Bradelygh

Hi, Would it be possible for you to scan the markov chains question? Thank you!
I wish I was allowed the paper , to take out with me :frown:

Original post by WKH

actually is it possible to scan the whole paper?
want to redo it again and check what have I done wrong

Thanks a lot

Did either of you do the groups Q? I really struggled with the (x , y)^5 = (1 , 1) bit, and the question afterwards - I wrote the same proof for both :/

Reply 23

IchiCC

Original post by Quadratic

Did either of you do the groups Q? I really struggled with the (x , y)^5 = (1 , 1) bit, and the question afterwards - I wrote the same proof for both :/

Did the same. I justified them both as something along the lines of (x,y)^5 = (x^5, y^5), and since (x,y) are elements of G, all of which of order 5 (except the identity), then (x,y)^5 = (1,1).

What do you all think the grade boundaries will be like for this paper?

Reply 24

Bradelygh

No , i was going to , it looked fairly straight forward to begin with, but i find the groups questions so time consuming, so I moved I did markov chains instead, which was okay, but since i'm dysbraxic I mis-interpret things sometimes, which makes comprehension papers and sometimes markov chains very difficult :frown:

! However, I thought it was an okay paper, although I missed out 12 marks!! Since I was rushed for time! Thank goodness this is part of my additional further maths AS!

I hope it went okay for you guys, there was only 4 of us doing the exam! We had to wait ages to do it, and kept in solitude, because of the clash with C4.

Reply 25

cleverbong

Does anyone did question 1 this morning figured out the coordinates of point D?
If so, how do you do that?

Reply 26

KristianF

Original post by Quadratic

However that is exactly what the question below asked for so I think I've done something wrong :s-smilie:

That was the same one i left blank (for exactly the same reason.. because I wanted to write that for the next question =p)

Edit: left it blank because of time would've put some jibberish in the hope of 1 mark otherwise

(edited 12 years ago)

Reply 27

KristianF

Original post by cleverbong

Does anyone did question 1 this morning figured out the coordinates of point D?
If so, how do you do that?

You had to work the scalar product through - i did it with alpha beta and gamma then substituted in for the longer lambda version of the x y z coordinates you got earlier in the equation of the line AD.

Sorta like below:

1/6 x (AD.(ABxAC)) = ±20

(AD.(ABxAC))= ±120

Giving you the two possible D's

Reply 28

Quadratic

Original post by IchiCC

That's how I justified it, but I basically included the next Q in my answer, so for the next Q I literally wrote - "see above", which looking back was a bad idea.

Personally I found the paper a lot harder than some of the past ones, but my friend said that may be down simply to the choice of questions. For example if lots of people did 1,2,3 and they were really easy, then they would all get a higher raw mark and thus knock down all those that did the hard questions!

Really though I thought the Vector questions were quite tricky - they weren't worded as straight forward as some past questions! But the groups one was the one that threw me the most, so I'm hoping that everybody else was thrown as well.

As far as grade boundaries... I've had a look at June '10 and that was 60 raw mark for an A (B=53). In my opinion I'd say we'd probably be looking at a similar 'hardness' of paper, so you should be looking for ~60 for an A. But no-one can know for sure until August :smile:

Reply 29

Quadratic

Original post by KristianF

Gutted because I started to do this but then my mind went blank how to do the scaler triple product. Basically I forgot you can use a matrix to solve it - had I done that I wouldn't be stressing as much as I am now, because all I could have lost would be the 3 marks from the groups question :/

Reply 30

cleverbong

Original post by Quadratic

I did the same thing as you but I can't manage to find position D.

Reply 31

Small123

Original post by KristianF

I did this but I did (AB.(ACxAD)), would this explain why i got one point rather than two?

Reply 32

cleverbong

Original post by Small123

I did this but I did (AB.(ACxAD)), would this explain why i got one point rather than two?

I did the same way as KristianF's (1/6(ABxAC).AD) but I only get one point.

Reply 33

cleverbong

Original post by Small123

I did this but I did (AB.(ACxAD)), would this explain why i got one point rather than two?

I think it is because 1/6(AB.(ACxAD))=+20 or -20
You can then sub it the equation AD to find out what the unknown value / constant is.

I forgot to make it equal to -20.

(edited 12 years ago)

Reply 34

WKH

Original post by A.Majid

Arite.. Bit of advice though, there's no point, you're only just gonna beat yourself up.

This isn't all of the paper, but all of it is up in the thread.

Yes I know, but I just couldn't let the questions get out of my mind :s-smilie:

anyway, thank you :smile:

Original post by Quadratic

Did either of you do the groups Q? I really struggled with the (x , y)^5 = (1 , 1) bit, and the question afterwards - I wrote the same proof for both :/

I did Q4, and me too i did something similar and wrote very little in part vi)

Original post by KristianF

I did this last part, used AD (5,4,3) to calculate it... think this is wrong ( I guess I misunderstood what the question is asking)

BTW, my teacher told me that we can do more than 3 questions and they will pick the best 3, is that true? becuase I did 4 questions and I think I screwed up Q1 :s-smilie:

(edited 12 years ago)

Reply 35

Small123

Original post by cleverbong

I think it is because 1/6(AB.(ACxAD))=+20 or -20
You can then sub it the equation AD to find out what the unknown value / constant is.

I forgot to make it equal to -20.

Ahhh of course, I was slightly on to something I guess but not really, I had the value of D as something like (5t,4t,-3t) or something like that and i got t=4 and thought I'd try t=-4 but decided not to in the end. Cheers for that! Made me feel a hell of a lot better about Q1 :p: