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Homework Help: PLease help for differential equation

  1. Jan 24, 2005 #1
    [tex] \frac{dy}{dt} = \frac{1}{(y+2)^{2}} [/tex] and y(0) =1

    th solution i got is [tex] y(t) = \sqrt[3]{3t-27} - 2 [/tex]

    the question asks find the domain of the definition of the solution

    Describe hwat happens when the solution as it reaches it'slimits of its domain. Why can't it be extended for more time?

    Looking at he function aid ti s CUBE ROOT shouldnt the domain be ALL REAL number?? So the limits are positive and negative infinity? So then the limits are positive and negative infinity respeectively??

    Input would be greatly valued!! Thank you!@
    Last edited: Jan 25, 2005
  2. jcsd
  3. Jan 25, 2005 #2


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    If you've typed your DE correctly then I think you have the wrong sign on the constant 27. Other than that, the derivative is undefined when y = -2 which occurs at t = -9 and makes it impossible to extend your soluion to t <= 9.
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