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    I completely do not understand part i) and ii). How did they draw that conclusion? Im completely lost.
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    Part i) Have you written out a few terms of C+iS?

    Part ii) Double angle formulae.
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    for part i I have, 1 + (n1)e^jtheta + (n2)e^2jtheta etc
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    and e^{2 i \theta}=(e^{i \theta})^2 so you have

    1+\binom{n}{1}e^{i\theta}+\binom  {n}{2}(e^{i \theta})^2+...
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    (Original post by BabyMaths)
    and e^{2 i \theta}=(e^{i \theta})^2 so you have

    1+\binom{n}{1}e^{i\theta}+\binom  {n}{2}(e^{i \theta})^2+...
    ahh, im not sure how that becomes (i+e^jtheta)^n though =/
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    (Original post by TimetoSucceed)
    ahh, im not sure how that becomes (1+e^jtheta)^n though =/
    Expand (1+e^{i \theta})^n then.

    It should become clear.
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    If you expand that wouldn't you just get 1+e^jntheta, im finding this very difficult
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    maybe the (n 1), (n 2) part is confusing me, ive always been quite confused on questions like these =/
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    (Original post by TimetoSucceed)
    If you expand that wouldn't you just get 1+e^jntheta, im finding this very difficult
    No. You should review the binomial expansion.
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    (Original post by TimetoSucceed)
    If you expand that wouldn't you just get 1+e^jntheta, im finding this very difficult
    No - what does the binomial theorem tell you about the expansion of (1+z)^n?
 
 
 
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