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Homework Help: Inverse function

  1. Nov 12, 2005 #1
    how do I find the inverse function of y=xSqrt -2X

    I have tried transposing it 6 times now but my results don't give the right answer for a 1:1 function for x<0
     
  2. jcsd
  3. Nov 12, 2005 #2

    HallsofIvy

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    I assume you mean to find the inverse function for [itex]f(x)= x\sqrt{-2x}[/tex] for x< 0. Finding an inverse function is exactly the same a solving an equation. The point of "inverse" is that if [itex]y= f(x)= x\sqrt{-2x}[/itex], then [itex]x= y\sqrt{-2y}[/itex]. Solve that equation for y. (You will need to square both sides and eventually solve a cubic equation.)
     
  4. Nov 12, 2005 #3
    No that's not what I meant but not to worry i found the solution with touch more effort.
     
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