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Homework Help: Need help solving the differential equation for the shape of a catenary?

  1. Feb 25, 2010 #1
    (Moderator's note: thread moved from "Differential Equations")

    The DE is y''=a*sqrt(1+(y')^2)

    I have no idea how to go about integrating it, I just started taking diff eq's and haven't taken calc in over a year. Any help would be appreciated, thanks!
     
    Last edited by a moderator: Feb 26, 2010
  2. jcsd
  3. Feb 25, 2010 #2
    A first step could be to define a new function u := y'

    Then rewrite:

    u'/sqrt(1+u^2) = a

    and then integrate both sides with respect to time or space or whatever variable y depended on.

    Torquil
     
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