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Homework Help: Particular integral problem

  1. Jan 9, 2007 #1
    1. The problem statement, all variables and given/known data
    I'm trying to find a particular integral to the differential equation on the attatched image, but I come up with two slightly different answers depending on the method I use. I suspect the problem (if it's not just me being very thick and making a silly algebra error) is the way arctan is defined but I can't see what I should do differently in either solution.

    3. The attempt at a solution
    Attatched.

    Thanks
     

    Attached Files:

  2. jcsd
  3. Jan 9, 2007 #2

    HallsofIvy

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    Science Advisor

    ?? You give just the answers and they look identical to me!
     
  4. Jan 9, 2007 #3
    One has a plus thi one has a minus thi for some reason.
     
  5. Jan 9, 2007 #4

    Gib Z

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    Homework Helper

    I think you mean phi, [tex]\phi[/tex]
    I havent read the question, I probably wouldn't understand it, but perhaps Halls was giving a hint that its equal to zero?
     
  6. Jan 10, 2007 #5
    My mistake sorry, meant phi. I think phi's only going to be zero in a special case, for most values of a,b,c,w it's going to be non-zero.

    Does anyone have any other suggestions? The second version is the one that works in the differential equation but I still can't see why the first one doesn't.
    Thanks
     
    Last edited: Jan 10, 2007
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