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    Hi,

    On a bit of work i've got to do, theres a question mainly based on binomial expansion and the last part of the question i am not sure what to do.

    Here is the question:

    (a) Find the binomial expansion of (1+x)^(1/3) up to the term in x^2
    (b) Show that (8+3x)^(1/3) ≈ 2 + 1/4 x -1/32 x^2 for small values of x
    (c) Hence show that ∛9 ≈ 599/288

    For part (a) i got 1 + 1/3 x - 1/9 x^2 and for part (b) i got the answer that it required but i haven't got a clue how to do (c)

    Any help would be appreciated

    Thanks
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    let 8 +3x = 9, then find the value of x and substitute it into ur expansion uve found
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    Put x=1/3 in (b)
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    x^1/3 is the cube root of 3
    so subbing a value for x shud give what you are looking for.
 
 
 
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Updated: February 11, 2010

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