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Homework Help: Solution for y + 1/y = x

  1. Jan 4, 2010 #1
    1. y + 1/y = x



    x = (1/2)[tex]\sqrt{x^2 - 4}[/tex] + 1/[(1/2)[tex]\sqrt{x^2 - 4}[/tex]]



    How do you come to the above conclusion by using the quadratic formula?
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Jan 4, 2010 #2

    diazona

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    First convert the equation you're given into a quadratic equation. It'll need to have one term with y^2, one term with just y, and one term that doesn't involve y at all. Can you think of a way to get it into that form? (Hint: multiply both sides of the equation by something)
     
  4. Jan 5, 2010 #3

    Mentallic

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    What exactly does "solution" mean?

    [itex]y\neq 0[/itex] so I'm sure you're not looking for the roots of that graph.
     
  5. Jan 5, 2010 #4

    HallsofIvy

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    I presume paridiso meant "solve for y as a function of x". That is what diazona is talking about, certainly.
     
  6. Jan 5, 2010 #5

    diazona

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    Indeed it is... I hope that's what the OP meant too.
     
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