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    (Original post by Aylia)
    It was probably only one or two marks - I made that mistake too.
    Thanks!!!
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    (Original post by ogs)
    prove that:
    d/dx (ln(cosecx+cotx)=-cosecx

    QED!
    y = lnt
    dy/dt = 1/t

    t = cosecx + cotx
    dt/dx = -cosecx(cosecx +cotx)

    dy/dx = dt/dx x dy/dt

    dy/dx = -cosecx(cosecx+cotx)/(cosecx+cotx)

    =-cosecx

    Thats how I got it anyway..
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    (Original post by imasillynarb)
    y = lnt
    dy/dt = 1/t

    t = cosecx + cotx
    dt/dx = -cosecx(cosecx +cotx)

    dy/dx = dt/dx x dy/dt

    dy/dx = -cosecx(cosecx+cotx)/(cosecx+cotx)

    =-cosecx

    Thats how I got it anyway..
    Well done smarty pants!

    Now leave us alone in our misery!!
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    For all those depressed about the exam, might make you feel a little bit better to work out how you did when comparing the AS results…

    I got 274 last year so 480-274 = 206

    So lets say I got 25/60 (if that!?!? thats me being optimistic ) so that’s about 41%, and since everyone found it hard lets jump that % up by 10% (how much do they bump it up by?) so that’s say 50%! ie 50/100

    So 206-50 = 156

    156 / 2 = 78

    So if I get about 78/100 in P2 and S2 then I could still get an A!

    Hmmm am I just making this all up to reassure myself?
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    I done edexcel,

    I didn't answer 1, 6, 7 or 8.

    I have found out I got the easier questions wrong.

    I have failed.

    It was just a stupidly hard P3 paper, there were 3-4 questions on there that were much more advanced than what I have seen on any of the past papers.

    Got a high B last year, I doubt I will be getting over 10-15 from this paper. Looks like I need full marks off P2 and S2

    Who ever heard of a 16 mark vector question!?

    ARGH!
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    (Original post by imasillynarb)
    y = lnt
    dy/dt = 1/t

    t = cosecx + cotx
    dt/dx = -cosecx(cosecx +cotx)

    dy/dx = dt/dx x dy/dt

    dy/dx = -cosecx(cosecx+cotx)/(cosecx+cotx)

    =-cosecx

    Thats how I got it anyway..
    Wish I'd done that. Instead I chose to write the full f '(x) / f (x) out and then try and simplify after converting all the sec's to cos' and the cosec's to sin's. I'm prettysure what I wrote doen made sense but I could not simplify it so I thought it best to write down what I thought the penultimate line was (i.e. -1 / sinx). Hopefully they won't think that I've made too bigger leap in my method and I should pick up a mark at least....*prays*
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    But seriously, that was the hardest exam Ive ever done. Im actually shocked it was so hard. Im happy though, as Ive actually gone and minced it! Couldnt do 8d) infact couldnt even start it, rest of it went well. I was so pushed for time, it was horrendous, I had 8 marks and only 10 minutes to get them in at the end
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    The first question I sort of cheated to get the answer.

    From the formular book I changed the question to In |tan1/2 x| and did it from there. Soooo much easier!

    No one could do question 8d but I did put something down for the rest. I think I may just scrape an A but it was VERY hard
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    (Original post by abc123)
    The OCR paper was just absolutely awful; I couldn’t have possibly got more than 25/60. That’s really strange though isn’t it? That students like myself, who have never scored less than 80% in previous maths papers, can fail so terribly on a P3 paper, there’s a real inconsistency with these papers.

    The worse thing is that I’ve never revised harder for any other exam…ever. I knew all the theory, and had scored well in the past papers, but still that was not nearly enough. I dunno what I could have done to prepare for a paper like that; certainly more revision wouldn’t have helped.

    And don’t get me started on that vector question….
    i'm the same... i had to learn how to revise. i really wish i hadn't bothered. i was clueless

    and that vector question was really weird, i got all muddled up on what point i was finding and then the mid-point of that and then the line from that to some other unknown point... result =losty of numbers and is+ js+ ks everywhere meaning nothing.

    i think OCR wins the prize for worst paper

    lou xxx
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    (Original post by Leekey)
    Wish I'd done that. Instead I chose to write the full f '(x) / f (x) out and then try and simplify after converting all the sec's to cos' and the cosec's to sin's. I'm prettysure what I wrote doen made sense but I could not simplify it so I thought it best to write down what I thought the penultimate line was (i.e. -1 / sinx). Hopefully they won't think that I've made too bigger leap in my method and I should pick up a mark at least....*prays*
    If you converted all the tanx's and secx's to sinx's and cosx's, you should have ended up with -cosecx also. The method is just a bit long-winded, but valid nonetheless.
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    (Original post by abc123)
    The worse thing is that I’ve never revised harder for any other exam…ever. I knew all the theory, and had scored well in the past papers, but still that was not nearly enough. I dunno what I could have done to prepare for a paper like that; certainly more revision wouldn’t have helped.

    And don’t get me started on that vector question….
    Exactly the same here! Im not a straight a student wen it comes to maths but my teacher said i'm capable of b, and I have never struggled on a paper like i struggled on that one. The thing that truely pisses me off abot that paper was absolutly nothing was standard, except the first trig question, i.e. questions i had spent many hrs revisin didnt even appear. I sometimes wonder if the ppl who make these thing care more about tryin to trick students, or enabling students to the grades the require and deserve for uni, themselves etc...
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    (Original post by Leekey)
    Wish I'd done that. Instead I chose to write the full f '(x) / f (x) out and then try and simplify after converting all the sec's to cos' and the cosec's to sin's. I'm prettysure what I wrote doen made sense but I could not simplify it so I thought it best to write down what I thought the penultimate line was (i.e. -1 / sinx). Hopefully they won't think that I've made too bigger leap in my method and I should pick up a mark at least....*prays*

    I did the smae but still didn't get the answer. It was really irritating knowing it was a 3 mark question, and that there had to be an easy way to solve it. I almost tried to work ou the differentials using first principles, theb luckily I remembered it was in the book :rolleyes: !
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    ok I just checked Edexcel

    http://www.edexcel.org.uk/VirtualCon...port_Jun03.pdf
    (GOTO PAGE 50 FOR GRADE BOUNDARIES)

    Last year's P3 paper grade boundaries were:

    51/75 to get a GRADE A which is about 68%

    So, I think this year its probably around the same boundary. I have setup a poll for Edexcel Students ONLY, and preferably for those P3 students who are estimated or are on a Grade A or B boundary.

    Visit my poll:
    http://www.uk-learning.net/t46833.html

    and please rate is excellent
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    (Original post by lou p lou)
    i'm the same... i had to learn how to revise. i really wish i hadn't bothered. i was clueless

    and that vector question was really weird, i got all muddled up on what point i was finding and then the mid-point of that and then the line from that to some other unknown point... result =losty of numbers and is+ js+ ks everywhere meaning nothing.

    i think OCR wins the prize for worst paper

    lou xxx
    Is it possible for papers tobe get thrown out on the basis that they wer to hard and not enough ppl did well enough...or is that only in my dreams
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    (Original post by Ollie)
    How did P3 go?

    Which questions did you find hard/easy?

    Was is a good exam or was it a repeat of last years horror?

    Which exam board?
    Edexcel. Nasty buggery little question called the last bit of q 8. I HATE IT!!!! Why will my method not work? :mad:
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    (Original post by lou p lou)
    i'm the same... i had to learn how to revise. i really wish i hadn't bothered. i was clueless

    and that vector question was really weird, i got all muddled up on what point i was finding and then the mid-point of that and then the line from that to some other unknown point... result =losty of numbers and is+ js+ ks everywhere meaning nothing.

    i think OCR wins the prize for worst paper

    lou xxx
    Hahahahahaha you actually made me laugh out loud about those vectors…. Soooo true I was just going round in circles… and getting so confused!
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    (Original post by sideshowbob)
    Edexcel: Waz the tangent, 12y-5x+38=0?
    The series expansion: 3-2x+11x^2, not valid x=0.5
    The equation of the circle: (x-5)^2 + (y-13)^2 = 169
    A = (0.5t + 0.5)^-2, then when t=0 A=4
    Factorisation: x(2x-1)(x+2)
    R = 6ln2 -(pi^2)/3
    i think i got, the same for the tangent,
    and for for the series expansion i think i got 3-x+11x^2
    same for circle
    A^(-1/2)=t^(-1)-1 i think
    same factorisation (i think)
    R= (pi^2)/18+6ln2

    i thought the exam was straight forward, i did part 8d, but it wasn't very elegant, all i did was know the direction it was going and the distance it was.

    form that i got 2 position vectors, and A which were all 14root2 distance apart.
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    Someone please do question 7. the rates of change one.. i got 4t^2=A+c

    Why is that wrong... ??
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    Trying to remember some of my answers....

    2a) 3
    b) p did infact =-1
    c) I worked out that (x-2) was a factor about 3 seconds before the end so didnt have time to do it all.

    3a) (x-5)^2 + (y-13)^2 = 13^2
    c) Something like 24y - 10x- 73 = 0??!??

    4) Lovely Question!!!

    5a) A=1 and B=2
    b) Something like 3 -7x +10x^2
    c) x=1/2 only satisfied one of the expasions therefore you can't use it.

    6a) x = 5sqrt3/2
    b) Nice and easy for me!!!
    c) Something like 6ln2 - pi/3 (can't remember if Im honest)

    7a) Got there in the end
    b) Wrote something stupid like t = A^4/3

    8a) alpha = -3
    b)s and t = 1 and 3
    c) Can't really remember
    d)It was infact 60 (i.e. cos0.5)
    e) Too hard!!!
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    What was the postion vector of where L1 and L2 intersected. -15i -?j +19k or somethin.
 
 
 
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