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    What is question 3 and question 6?
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    (Original post by wr123)
    I DID !!
    Yayyyy l i calculated the are of 1 wrong and got something weird, well at least still get some mark
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    What did everyone get for question one because I think I got something like -2<x<1.

    Did you multiply both sides by (x+1)^2 and (x+2)^2?
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    (Original post by Ewanclementson)
    Answers - let me know if they need to be edited (edit - typo on 5 fixed)
    1) -2<x<-root2 -1<x<root2
    2) shown x(x^2-3x-9)/2(x+2)
    3)e^ipi(1/24, 13/14, -11/24, -23/24) shown
    4) r/q(1-e^-(q/p)t) (2sinx-cosx+e^-2)/5
    5) Coefficients are 1/16, -5/16, 10/16 shown
    6) coefficients are 1 2 2 8/3 then shown
    7) Ax^2+Bx-1/12x^(-2)
    8) 21/4, (+-)arcos(3/4) 32.519 which I think was 3root7/4-11arcos3/4+49pi/4
    Hope this helps everyone!
    How did you get those answers to 3?
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    For question 3 did the answers for theta have to be between pi and -pi? I didn't read the question
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    Ax+Bx^2-1/12x^-2
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    (Original post by cjlh)
    Didn't get -3, got -9 though I think. If this is wrong how many marks do people think would be lost?
    Hopefully two or three at most, that was the one bit i got wrong- i got -3n but got -11 cos i took away rather than added.
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    when everyone's complaining they couldn't integrate e2x sinx, meanwhile I didn't even have e2x sinx anywhere on my paper


    Posted from TSR Mobile
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    (Original post by fghj1)
    For question 3 did the answers for theta have to be between pi and -pi? I didn't read the question
    No, it didn't specify.
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    (Original post by smartalan73)
    How did you get those answers to 3?
    The second value for theta should be 13/24 not 13/14 typo?
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    (Original post by Ewanclementson)
    Yes but on the LHS we have e^2theta*x and so this 1/5 becomes (e^-2theta)/5
    **** sake😑
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    How many marks for the last question? I've messed up so much


    Posted from TSR Mobile
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    Answers - let me know if they need to be edited (edit - typo on 5 and 3 fixed)
    1) -2<x<-root2 -1<x<root2
    2) shown x(x^2-3x-9)/2(x+2)
    3)e^ipi(1/24, 13/24, -11/24, -23/24) shown
    4) r/q(1-e^-(q/p)t) (2sinx-cosx+e^-2)/5
    5) Coefficients are 1/16, -5/16, 10/16 shown
    6) coefficients are 1 2 2 8/3 then shown
    7) Ax^2+Bx-1/12x^(-2)
    8) 21/4, (+-)arcos(3/4) 32.519 which I think was 3root7/4-11arcos3/4+49pi/4
    Hope this helps everyone
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    Anyone predicate this years grade boundaries? How many marks for A*??
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    (Original post by daniella_n)
    when everyone's complaining they couldn't integrate e2x sinx, meanwhile I didn't even have e2x sinx anywhere on my paper


    Posted from TSR Mobile
    Yeah everyone went on about that question after. I thought it was just C4?
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    How did I manage to **** up question 8b
    There goes my A*

    I think I integrated the curves with the opposite limits or something. Urgh.
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    How were you supposed to do Q4? I did i.b.p. twice to get I = something + (1/4)I, but I don't think that's on the A-level syllabus.
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    (Original post by sweeneyrod)
    No, it didn't specify.
    Phew, thank you, I had pi/24 13pi/24, 25pi/24, 37pi/24, Is that Ok then?
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    (Original post by Mathemagicien)
    I did question 4 directly, not by parts, using exponential version of sin x.
    Doesn't that require integrating imaginary numbers?
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    (Original post by Mathemagicien)
    Can't see the image (at school), is it the exponential version of sin, or some even nicer way?
    Integrand is the imaginary part of e^(2+i)x.
 
 
 
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