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Diff EQ question

  1. Feb 15, 2005 #1
    When you are trying to determine the general solution of a homogeneous linear ordinary differential equation, after you find the roots, how do you decide which goes with c1 and which goes with c2?



    Factoring the auxiliary equation


    is there some kind of convention as to which gets named as m1 and m2?
    It seems like every time I do one of these kinds of problems, my answer is the opposite of the books. Is there any difference between

    y=c1e^(x)+c2e^(2x) and y=c1e^(2x)+c2e^(x)?
  2. jcsd
  3. Feb 15, 2005 #2
    c1 and c2 are arbitrary constants which must be determined by initial conditions only. so there is no difference if you interchange them
  4. Feb 15, 2005 #3
    That's what I was hoping for, thanks.
  5. Feb 15, 2005 #4
    No, they have no different....... you can write it either way.....

    It depend on the publisher...
  6. Feb 15, 2005 #5


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    Read the result from right to left.I'm sure it will coincide with yours...

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