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Homework Help: Haunted House Door

  1. Apr 28, 2005 #1
    Hi all. I am in the middle of a ridig body rotation problem. Anyways, I have x double dot = sin(x) and i need to find what x dot is. x is a function of time 't' and I just have no idea how to get it. so it is d^2x(t)/dt^2=sin(x(t)) where x(t) is a function and i need to find dx(t)/dt.

    Any help would be great, thanks!!
     
  2. jcsd
  3. Apr 29, 2005 #2

    learningphysics

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    Homework Helper

    Let a=dx/dt

    da/dt=d^2x/dt^2

    Therefore
    da/dt = sin(x)

    (da/dx)(dx/dt) = sin(x)

    (da/dx)(a) = sin(x)

    a da = sin(x) dx

    And you can get a by integrating both sides...
     
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