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    For the complex roots question I messed up and got my r wrong but I got the 4 values of theta right, how many marks out of 5 do you think I'll lose?
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    (Original post by NamelessPersona)
    This is what I did but I got a different answer to most people :/ (got area as 71.00)
    I got that too... I'm not sure what happened. Hopefully it is only because I typed the stuff into the calculator wrong (because then I will lose less marks :dontknow:)
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    (Original post by Baldwinator)
    I just can't figure out what i did wrong, i checked all my working over loads.


    Posted from TSR Mobile
    I did what you did at first and then realised what to do. When you differentiate dy/du to get d^2y/du^2, you're doing it with respect to x so you have to also times it by du/dx which is 1/x so when you use product rule that term also becomes 1/x^2.
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    For the complex roots one I did k=0,1,2,3 instead of k=-1,0,1,2. Would this be a problem? Not sure if it matters if you give alternate solutions as long as all 4 k values are consecutive.
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    Knew how to do the majority of the methods but would **** up when tidying up my answers. Nice one.
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    (Original post by electrifeye)
    For the complex roots one I did k=0,1,2,3 instead of k=-1,0,1,2. Would this be a problem? Not sure if it matters if you give alternate solutions as long as all 4 k values are consecutive.
    If the question said -π<x<π you must use -1 instead of 3 as 3 gave a value over π. Did it say that range? If not maybe you are ok.
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    (Original post by electrifeye)
    For the complex roots one I did k=0,1,2,3 instead of k=-1,0,1,2. Would this be a problem? Not sure if it matters if you give alternate solutions as long as all 4 k values are consecutive.
    Question didn't specify a range, k=0,1,2,3 would be accepted.
    All the angles ended up between 0 and 2pi anyway, which was nice.
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    How many marks would I lose if I used x instead of theta for 4b?
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    Well.. Ok. As much as I was panicking during that exam, I've only definitely made one mistake on 4ii. Not like everybody else struggling to integrate it, I used a nice method of using IBP twice to get it in a form where I could substitude ye^2theta in. In my wisdom, I managed to think 1 - 1/4 = -3/4. So all my answer was wrong by a sign change (which is such a stupid mistake to make, I did it in c1 last year).

    There was plenty of answers I could check on this which was good (especially the series question, which was weird, the de moivres solutions, the taylor series and the polar coordinates, 32.5 or something I think, on attempt 2).
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    is the mark scheme out?
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    Can anyone remember the question for 4ai) - the first order differential with p q and r??
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    FP2 more like FPpoo
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    (Original post by federer98)
    Can anyone remember the question for 4ai) - the first order differential with p q and r??
    It was either

    p\dfrac{dx}{dt}+qt = r

    or

    q\dfrac{dx}{dt}+pt = r

    with x = 0 when t = 0
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    Screwed up Methods of Differences because I messed up the algreba. Screwed up First Order DE because I was too tired to figure out how to solve an unfamiliar integral. Screwed up Polars because I typed the wrong thing in my calculator but at least that's less marks lost.
    RIP A*. If I get a difficult FP3 then I can kiss it goodbye.
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    (Original post by Mathemagicien)
    I did question 4 directly, not by parts, using exponential version of sin x.
    How was it?

    I had quite a few exams after FP2, so I just came to TSR. I think I got 75/75 but I am not sure if I lost some marks due for the fact that everyone in here is crying about some integral with integration by parts when I don't remember doing any IBP in the exam. I finished early so I was able to check my solutions multiple times. What do you mean by exponential version of sin x?





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    (Original post by JamieOH)
    If the question said -π<x<π you must use -1 instead of 3 as 3 gave a value over π. Did it say that range? If not maybe you are ok.
    I did this too, I'm fairly sure it didn't give a range
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    Does anyone have the equation for 4part i?
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    ~550 people have now voted on this poll; http://www.thestudentroom.co.uk/show....php?t=4150121

    205 - Very hard
    181 - Hard
    85 - OK
    79 - Very easy
    15 - Easy

    If you haven't voted yet, make sure you do.

    My predictions:
    67 - A* (maybe 66)
    61 - A (maybe 60)
    54 - B
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    For the polar area question I did cardioid minus circle instead of cardioid plus circle (sorry, I forgot which one was C1 and which one was C2), giving me an answer of about 15.272, but the integration should be correct as my calculator confirmed it, so how many marks might I lose for that part question?
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    how do you integrate e^xsinx then?
 
 
 
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