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    Okay, I'm really stuck on this question...

    Find the first four terms in the expansion of (1 + x + x^2)^7 in ascending powers of x.

    I understand you write it as [(1 + x) + x^2]^7...
    However, I'm not too sure about what to do and hte methods that I have been using do not lead to the correct answer.

    Thanks! :confused:
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    I would be surprised if this was C2.
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    You would do better to write it as [1+(x+x^2)]^7, or better yet [1+(x(1+x))]^7

    Why? Because in those forms it is much easier to see which terms will be of order x^4 or higher, and therefore ignorable (since you are looking only for the first 4 terms).
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    (Original post by steve2005)
    I would be surprised if this was C2.
    It is but rarely comes up.
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    (Original post by mcp2)
    It is but rarely comes up.
    OK Thanks.
 
 
 
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