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How would I expand this? :/

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    (1+x+x^2) ^1/2

    The question says expand as a series so I assumed it means using the binomial expansion for fractional powers, I'v attempted it, but I know its wrong, and I may sound stupid, but I'v never used binomial when there is three terms in the bracket! Lol any help will be appriciated


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    You need to expand (1+y)^1/2

    Then substitute (x+x^2) for y
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    (Original post by Aneesa.x)
    (1+x+x^2) ^1/2

    The question says expand as a series so I assumed it means using the binomial expansion for fractional powers, I'v attempted it, but I know its wrong, and I may sound stupid, but I'v never used binomial when there is three terms in the bracket! Lol any help will be appriciated


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    Expand  [ 1 + (x+x^2)]^{\frac12}
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    You just take (x+x^2) as 1 term.

    So you get [1+(x+x^2)]^1/2
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    (Original post by TenOfThem)
    You need to expand (1+y)^1/2

    Then substitute (x+x^2) for y
    That's what I done, I get the wrong answer :/

    Could you show me some steps? Maybe I'v gone wrong in my working somewhere..



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    (Original post by Aneesa.x)
    That's what I done, I get the wrong answer :/

    Could you show me some steps? Maybe I'v gone wrong in my working somewhere..



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     \displaystyle [1+(x+x^2)]^{\frac12} = 1 + \frac12 (x+x^2) + \frac{\frac12 \left( \frac12 - 1 \right) }{2!} (x+x^2)^2 + \ldots
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    (Original post by Aneesa.x)
    That's what I done, I get the wrong answer :/

    Could you show me some steps? Maybe I'v gone wrong in my working somewhere..
    Post your working.
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    Oh wait I got it now lol .. silly mistake -___-

    Thanks everyonee


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    I don't understand this at all, is it C2 level stuff?

    Because in C2 you never do binomial to the power of a 1/2.

    Can someone show me how you do a binomial expansion to the power of a 1/2 please?
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    (Original post by violetheart)
    I don't understand this at all, is it C2 level stuff?

    Because in C2 you never do stuff to the power of a 1/2.

    Can someone show me how you do a binomial expansion to the power of a 1/2 please?
    It is C3
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    (Original post by violetheart)
    I don't understand this at all, is it C2 level stuff?

    Because in C2 you never do binomial to the power of a 1/2.

    Can someone show me how you do a binomial expansion to the power of a 1/2 please?
    (Original post by TenOfThem)
    It is C3
    In edexcel it is C4.
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    (Original post by violetheart)
    I don't understand this at all, is it C2 level stuff?

    Because in C2 you never do stuff to the power of a 1/2.

    Can someone show me how you do a binomial expansion to the power of a 1/2 please?
    There is a different formula for binomial expansions with fraction or negative powers, don't worry about it yet if you're doing C2


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    (Original post by raheem94)
    In edexcel it is C4.
    Maybe C4 then
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    Ahh, thankyou, I was pretty worried then I'm just starting C3 but I was wondering if I missed something important.

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