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Homework Help: Just a confirmation

  1. Jun 29, 2006 #1
    I just wanted to make sure I differentiated this correctly before I started graphing it:

    y=x^2/1-x^2

    y' = (2x)/(1-x^2)^2

    y''=(2+6x^2)/(1-x^2)^3
     
  2. jcsd
  3. Jun 29, 2006 #2

    Hootenanny

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    I don't think that it is quite correct. I believe you are missing a term for your y' derivative (I haven't checked your y''). How did you differentiate? Using the quotient rule?
     
  4. Jun 29, 2006 #3
    Yes, I used the quotient rule:

    y'= (1-x^2)(2x)-(-2x)(x^2) / (1-x^2)
    y'= 2x-2x^3+2x^3 / (1-x^2)
     
  5. Jun 29, 2006 #4
    Don't forget to square the denominator ;)
     
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