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Homework Help: Differential equation problem

  1. Mar 4, 2008 #1
    1. The problem statement, all variables and given/known data

    Find the value of k for which the constant function x(t)=k is a solution of the differential equation 9t[tex]_{2}[/tex][tex]\frac{dx}{dt}[/tex] -3x + 7 = 0.

    The answer: k -2.33

    2. Relevant equations


    3. The attempt at a solution

    I'm a little confused on where to start...I was under the impression I had to factor and find what values would set the function equal to zero, so I did that, but it didn't come out right. Help?
  2. jcsd
  3. Mar 4, 2008 #2
    Since x(t)=k doesn't have a term including t, we have dx/dt=0.The rest is just simple arithmetic!
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