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How do I solve this differential Equation

  1. Apr 17, 2015 #1
    1. The problem statement, all variables and given/known data
    y3(dy/dx) = (y4 + 1)cosx

    2. The attempt at a solution

    I solved for the homogeneous equation which is y = Ce-sinx Where C is some constant

    for the particular solution I tried Asinx + Bcosx where A and B are constants but when subbing in it's gets very messy.

    How should I do this?

    Thank you
  2. jcsd
  3. Apr 17, 2015 #2
    This looks like a variables separable problem.

  4. Apr 17, 2015 #3
    Try some algebra to separate the variables and then integrate both sides.
  5. Apr 17, 2015 #4


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    You shouldn't. That method is for a linear (usually constant coefficient) DE.
  6. Apr 18, 2015 #5
    Thanks for the replies, it was just a simple separation of variables problem. It's strange how you sometimes forget the basics as your knowledge grows.
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