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Differential equations - solving initial value problem

  1. Jan 20, 2009 #1
    1. The problem statement, all variables and given/known data
    Solve the given initial value problem and determine how the interval in which the solution exists depends on the initial value y0.

    y' = -4t/y, y(0) = y0

    2. Relevant equations

    3. The attempt at a solution
    I solved the DE and got to:

    y = +/- sqrt(C - 4t^2)

    Plugging in y_0 for y when t = 0, I get:

    y = +/- sqrt( (y_0)^2 - 4t^2 )

    I'm pretty sure this is the right, but how do I answer the last part of the question? Figuring out the how the interval depends on initial value? thanks
  2. jcsd
  3. Jan 20, 2009 #2


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    Staff Emeritus
    Science Advisor
    Gold Member

    Usually, unless stated otherwise, one would assume that the solution must be real-valued.
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