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Homework Help: Division with variables (I think I'd call this double division)

  1. May 25, 2006 #1
    I don't even know where to start with this question, someone help please.

    I don't know how to LaTeX this question so please bare with me:

    ( ( x / y ) - ( 4y / x ) ) / (x + 2y)

    It's two fractions over a binomial.

    Hope this isn't to unclear :(
     
  2. jcsd
  3. May 25, 2006 #2

    Alkatran

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    Click this for the code to make it:
    [tex] \frac{\frac{x}{y} - \frac{4y}{x}}{x + 2y} [/tex]

    Now the question on everyone's mind is: what do you actually have to do with this? Simplify it?
     
    Last edited: May 25, 2006
  4. May 25, 2006 #3
    Yah, sorry about that, and thanks for the LaTeX code. I'm supposed to simplify it but after setting it up like this [tex] \frac{x}{y} - \frac {4y}{x} \times \frac{x + 2y}{1} [/tex] (I think that's proper form anyways) I don't know what else to do.
     
  5. May 25, 2006 #4
    dont know if this is right but it looks good to me

    First find the comon denominator in the top fraction

    {(x^2-4y^2)/(xy)}/(x+2y)
    multiply by the inverse

    (x^2-4y^2)/(x^2y+2xy^2)

    then diference of squares?

    (x+2y)(x-2y)/(xy)(x+2y)

    then cancel

    (x-2y)/xy


    Anyone know a good LaTeX tutorial? I would likke to post more and using LaTeX is just so much prettier :)
     
    Last edited: May 25, 2006
  6. May 25, 2006 #5

    VietDao29

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    Please, don't show COMPLETE solution. You can guide him, and should let the OP do it him/herself. Showing solutions can be good in some cases, like when the OP has made a great deal of effort trying to solve the problem, but still cannot get the correct answer. But showing solution without any explanation, or without the OP's having shown his/her work, it can be very bad.
    You can take some time to readthe rules.
    ------------------------
    There's a sticky Introducing LaTeX Math Typesetting in the board Math & Science Tutorials (the first board from the top). There are 3 pretty good .PDF files there.
     
  7. May 26, 2006 #6


    You are probably right , sorry about that.
     
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