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Homework Help: Checking binomial series

  1. Feb 4, 2010 #1
    hi there im abit stuck here. i got a q saying :
    in binomial expansion of (3-2/x)^9 find the 5th term using the general term of the binomial expansion and check your answer


    used formula

    =N!/(n-r)!r! * A^(n-r) * b ^ r

    r= 4
    a= 3
    b= - 2/x

    got a answer of -489888/x^4

    How do i go about checking my answer??
  2. jcsd
  3. Feb 4, 2010 #2


    Staff: Mentor

    My answer is like yours, but without the negative sign.
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