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Homework Help: A Linear Diet Model

  1. Mar 19, 2006 #1
    I am working on solving a linear diet problem. I am given a differential equation. The problem basically requires me to solve the D.E., then plug 'n chug. I have gone over the solution to the D.E. over and over again. A fellow calculus student has also looked over the math and cannot find the error. Quite possibly there is no error and I am misinterpretting something. I end up with a negative inside of a natural logarithm, but I cannot find a way to get it out. Additionally, I have tried simply using the absolute value of the log, but I don't think this is correct.

    I have put the question along with my work into a PDF file located http://mlowery.t35.com/Special_Project_Weight_Loss.pdf" [Broken]

    If anyone could point out my error/misinterpretation, I would greatly appreciate it.

    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Mar 19, 2006 #2


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    Why did you call k the initial weight? The initial weight is w(0). (Assuming the initial time is t = 0)
  4. Mar 19, 2006 #3
    Well my new answer seems more logical :)
    Thank you so much Hurkyl.
  5. Mar 20, 2006 #4


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    I presume you editted your answer based on what Hurkyl said. I solved the d.e. using a different method but got exactly the answer you did.
    Good work!
  6. Mar 20, 2006 #5
    Yes, I did edit my answer based off of Hurkyl's advice. Thank you HallsofIvy for checking it as well.

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