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Impossible problem?

  1. Nov 1, 2009 #1

    I'm

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    1. The problem statement, all variables and given/known data

    is( X^2 )y + (Y^2)x = 6, then the second derivative at the point (1,3) is ?

    2. Relevant equations



    3. The attempt at a solution

    I don't see how this is possible, when I plug in 1 and 3 it comes out as 9 = 6 which isn't true. Can someone tell me if this is wrong? or if the problem is written badly?
     
  2. jcsd
  3. Nov 1, 2009 #2

    lanedance

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    fair point, but i get 12

    ( X^2 )y + (Y^2)x = (1)3 = (3^2)1 = 12
    are you maybe missing a factor of 2?
     
  4. Nov 1, 2009 #3

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    you're right its 12 but how can I solve the problem?
     
  5. Nov 2, 2009 #4
    Have you tried solving for the second derivative first?
     
  6. Nov 2, 2009 #5

    lanedance

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    well as you point out, (1,3) is not a point on the curve defined by
    (x^2)y + (y^2)x = 6, so you can't really

    can you write the exact question?
     
  7. Nov 2, 2009 #6

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    Thats the equation I was given.
     
  8. Nov 2, 2009 #7

    lanedance

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    it may help if you write the whole question verbatim

    but as already said, (1,3) is not a point on the curve defined by (x^2)y + (y^2)x = 6, so the question does not make sense - it is undefined
     
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