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    Having trouble with question 8 on the AQA FP2 January 2012 paper, specifically part c and d. If anyone would be willing to help I would be extremely grateful.
    Here's the link: http://filestore.aqa.org.uk/subjects...2-QP-JAN12.PDF

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    (Original post by IMZL)
    Having trouble with question 8 on the AQA FP2 January 2012 paper, specifically part c and d. If anyone would be willing to help I would be extremely grateful.
    Here's the link: http://filestore.aqa.org.uk/subjects...2-QP-JAN12.PDF

    Thanks
    What have you tried?
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    (Original post by joostan)
    What have you tried?
    I haven't gotten far at all really. Only thing I can see is pairing z+1/z and z^2+1/z^2, to get 2cos2π/5 and 2cos4π/5?
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    (Original post by joostan)
    What have you tried?
    I just got part c I think. Using part b to multiply out corresponding linear factors( i.e. (z-e^2πi/5)(z-e^-2πi/5)) noticing e^-2πi/5+e^2πi/5=2cos2π/5 and dividing by z^2?
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    For part (d) find w^2 and see how you can write z^2 + z^(-2) in terms of only w and w^2 this should let you get a quadratic in w.
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    (Original post by Zacken)
    For part (d) find w^2 and see how you can write z^2 + z^(-2) in terms of only w and w^2 this should let you get a quadratic in w.
    Oh yeah, got it, thanks!
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    (Original post by IMZL)
    I just got part c I think. Using part b to multiply out corresponding linear factors( i.e. (z-e^2πi/5)(z-e^-2πi/5)) noticing e^-2πi/5+e^2πi/5=2cos2π/5 and dividing by z^2?
    This is correct, by the way. :-)
 
 
 
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