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Homework Help: Decay equation

  1. Aug 5, 2010 #1
    1. The problem statement, all variables and given/known data
    X--Y----Z, starting with X only


    2. Relevant equations
    y=C(e^-(alpha*t) -e-^beta*t)

    C, alpha, beta constts SUCH THAT C >0 0<alpha <beta

    show dy/dt= 0 imply t = 1/ (beta -alpha )*ln (beta/alpha)


    3. The attempt at a solution

    no idea!
     
  2. jcsd
  3. Aug 5, 2010 #2

    HallsofIvy

    User Avatar
    Science Advisor

    Well, since it asks you to show that dy/dx= 0, have you differentiated
    [tex]y= c(e^{-\alpha t}- e^{\beta t}[/tex]?

    Set that derivative equal to 0 and solve for t.
     
  4. Aug 7, 2010 #3
    Thanx, I trying to differentiate. Bt now sorted out!! cheers!!
     
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