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Homework Help: Urgent: Need help with solving differential equations

  1. Apr 17, 2010 #1


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    Hi guys,

    So I have gotten my assignment for my DE class and fortunately for me, someone had already posted up the questions on the net. Here it is:

    http://www.cengage.com/math/book_con...e/Project3.pdf [Broken]

    I have posted this in the DE section, which i think is the wrong section to post in.

    Anyway I have managed to do a number of the questions as below together with the answers:

    1) sinh [-ln x] - sinh [-ln w] = y/vx : whereby v= Vr/ Vs
    2) Have yet to try
    3) From the answer i got in (1), I just substituted y= 0 and x= -w, and i get something like this: Vr/ Vs = 0 ...... and since Vr = 0 and Vs is any value greater than 0, it is proven what the question wants... Not sure though if it is right :S Please help me check...
    4) No prob with this, got it proven
    5) r= wsec θ/(sec θ + tan θ)^Vs/Vr
    6) I just dont know what values to sub in to solve it..please help
    7) No prob with this too, got it done
    8) Done, got y=2.5 Bubba survives

    So guys, I hope you all can help me figure out how to do number 6 and perhaps see if my number 3 is right?

    Thanks so much...

    Best regards
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Apr 18, 2010 #2


    Staff: Mentor

    The link you supplied goes to http://www.cengage.com and no further. It doesn't show the problems you mention.

    If you want help on 6 and a confirmation of your answer on 3, please post these problems and the work you have done.
  4. Apr 19, 2010 #3


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    Hmm, thats weird, try going to google

    Then google: Differential Equations- Swimming in salmon

    Its the first link...

    Hope you guys can help. Thanks a bunch!
  5. Apr 19, 2010 #4


    Staff: Mentor

    We shouldn't have to search the internet to find your problem. If you want help, please post your problem and the work you have done.
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