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Homework Help: Showing a system is invariant

  1. Mar 4, 2012 #1
    1. The problem statement, all variables and given/known data
    Show that I = log(u)-u+2log(v)-v is an invariant of the following system
    [itex]
    \dot{u}=u(v-2)[/itex]

    [itex]
    \dot{v}=v(1-u)
    [/itex]

    2. Relevant equations

    3. The attempt at a solution
    The question was given on a homework assignment, but I have very little idea what it is asking for and even less of an idea of how to solve it.
     
  2. jcsd
  3. Mar 4, 2012 #2

    tiny-tim

    User Avatar
    Science Advisor
    Homework Helper

    hi rg2004! :smile:
    it just means that I-dot is zero :wink:
     
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