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Homework Help: Please hint me

  1. Apr 17, 2008 #1
    [SOLVED] please hint me

    1. The problem statement, all variables and given/known data
    28. What is the coefficient of [tex]x^{88}[/tex] from
    [tex](x+1)(x+2)(x-3)(x+4)(x+5)(x-6)...(x+88)(x+89)(x-90)[/tex].

    29. Find x from this equation [tex]\frac{108}{\sqrt{x^2-2916}}=\frac{378-x-\sqrt{x^2-2916}}{x+54}[/tex].


    2. Relevant equations



    3. The attempt at a solution
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Apr 17, 2008 #2

    tiny-tim

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    Science Advisor
    Homework Helper

    Hi mercedesbenz! :smile:

    ok … a hint, as you asked for …

    First, try answering: what are the coefficients of [tex]x^{90}[/tex] and of [tex]x^{89}[/tex] ? :smile:
    You can simplify this slightly, before solving it:

    Hint: what is √2916? What is 378/√2916? :smile:
     
  4. Apr 18, 2008 #3
    Thank you so much I've already solved it.
     
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