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Homework Help: What to take as p(x,y) and q(x,y) with partials

  1. Oct 3, 2006 #1
    http://album6.snapandshare.com/3936/45466/845529.jpg [Broken]
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Oct 4, 2006 #2


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    Homework Helper

    Your DE is P(x,y)dx + Q(x,y)dy = 0 and you want to find out if it is exact.

    The equation will be exact if [tex]\frac{\partial P}{\partial y} = \frac{\partial Q}{\partial x}[/tex].

    You have P(x,y) = 5x + 4y giving [tex]\frac{\partial P}{\partial y}=4[/tex]

    And Q(x,y) = 4x - 8y² giving [tex]\frac{\partial Q}{\partial x} = 4[/tex]

    Have a look at http://www.sosmath.com/diffeq/first/exact/exact.html" [Broken] and see if it helps.
    Last edited by a moderator: May 2, 2017
  4. Oct 4, 2006 #3
    Great, I took a quick glance at the sight and it looks as if that will help a lot. I will have to take a deeper look into it later this afternoon, but I just wanted to say thanks for your imput. I'll let you know if I have any more problems. =p

    thanks!! ^_^
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