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Prove that if x≠0 then if y= 3x^2+2y/x^2+2 then y=3

  1. Aug 24, 2013 #1
    suppose that x and y are real numbers. Prove that if x≠0 then if y= 3x^2+2y/x^2+2 then y=3
     
  2. jcsd
  3. Aug 24, 2013 #2

    mathman

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    y(1-2/x2) = 3x2 + 2

    y = (3x4 + 2x2)/(x2-2)

    Doesn't look constant.
     
  4. Aug 24, 2013 #3

    rubi

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    It looks like he wanted to write
    [tex]y = \frac{3x^2+2y}{x^2+2}[/tex].
    Then it works out:
    [tex]y x^2 + 2y = 3x^2 + 2y \Leftrightarrow y x^2 = 3 x^2 \Leftrightarrow y = 3[/tex]
     
  5. Aug 25, 2013 #4

    mfb

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    Staff: Mentor

    This is not an acceptable way to ask for help at homework problems. In addition, it is in the wrong forum.
     
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