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Homework Help: Help with showing work

  1. Jan 13, 2009 #1
    1. The problem statement, all variables and given/known data

    The original problem asks for the inverse of f(x) = (1-sqrt(x))/(1+sqrt(x))
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    2. Relevant equations

    3. The attempt at a solution

    When I swap the variables and get to x = (1-sqrt(y))/(1+sqrt(y)), I am having problems showing the steps to get to my final answer, which I know by solving with my 89 is Y = (x-1)^2/(x+1)^2, could you help me with the steps in between.
  2. jcsd
  3. Jan 13, 2009 #2
    First solve for sqrt(y), can you do that?
  4. Jan 13, 2009 #3
    having trouble solving for sqrt(y), I know I'll have to do the subtraction before I can square both sides by looking at the answer, that's what is throwing me off, should I be trying to split the fraction into multiple fractions first?
  5. Jan 13, 2009 #4
    Multiply both sides by 1 + sqrt(y), then move everything with sqrt(y) on one side and everything without on the other, what do you get?
  6. Jan 13, 2009 #5
    i got (x)(sqrt(y) + sqrt(y) = 1 - x, or should I not be distributing the x?
  7. Jan 13, 2009 #6
    never mind I see it now, thanks for your help
  8. Jan 13, 2009 #7
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