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Homework Help: Simple Hyperbolic Functions

  1. May 30, 2007 #1
    Cosh u = (2sinh u) -1

    Working from definitions

    http://img118.imageshack.us/img118/3271/eusm4.png [Broken]

    Its a worked example from the book, which isnt very well explained. The only step i struggle on is from how the managed to get all the u's positive (step 2). I plugged some numbers in for u and find the two equations dont equal each other anyway. What am i doing wrong?

    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. May 30, 2007 #2

    George Jones

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    What happens when you multiply the second equation in your linked image by e^u?

    Right, this equation isn't satisfied by all values of u. You are supposed to find the values of u for which it is satisfied.
  4. May 30, 2007 #3
    gotcha thx!
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