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Solve It!

  1. Apr 11, 2003 #1
    I have decided to post an exercise and see what happens. You can post your own problems, too, if you wish. Have fun with this one!

    Solve the following differential equation:

    y′′′ = y
  2. jcsd
  3. Apr 11, 2003 #2
    y(t) = a*exp(b*t) where b^3 = 1.
  4. Apr 11, 2003 #3


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    The general solution is of the form


    where c1, c2 and c3 are (complex) constant that can be fixed by initial conditions and

    This can be re-written in the real field as

    y(x)=exp(x)* c1 + A*exp(-x/2)*cos(sqrt(3)*x+B) )

    where A and B are new constants depending on c2 and c3 only.
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