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Homework Help: Need help solving an inequality.

  1. Nov 7, 2006 #1
    I figured out the answer to the question I originally posted in this thread, but, I have another.

    I am trying to solve [tex]2+x^{\frac{-3}{2}}>0[/tex]

    I end up with [tex]x>(-2)^{\frac{-2}{3}}[/tex] by just putting the 2 on the other side and solving. This is not the right answer though... what am I doing wrong? Thanks

    Thats a 2+x^(-3/2) btw. (for the top tex) and a (-2)^(-2/3) for the bottom tex.
     
    Last edited: Nov 7, 2006
  2. jcsd
  3. Nov 7, 2006 #2

    radou

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    Homework Helper

    Try to look at the inequality f(x) > 0, where f(x) = 2 + x^(-3/2). Analyze the function.
     
  4. Nov 7, 2006 #3
    Okay, I guess it makes more sense to do it that way :).

    Since there is a x under a square root sign, the domain is [0,inf) and since the squareroot is always positive, the function is always > 0 :). Thanks,
     
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