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Homework Help: Help for Dynamics! Continuous Motion

  1. Jul 30, 2011 #1
    Can someone tell me how to obtain the figure in red circle? I've trying out on my own but can't get that.
     

    Attached Files:

  2. jcsd
  3. Jul 30, 2011 #2

    tiny-tim

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    Welcome to PF!

    Hi JamieShumJr! Welcome to PF! :smile:
    You're asking why is ∫ (0.8t + A)-1/2 dt = (2/0.8)(0.8t + A)1/2

    apply the https://www.physicsforums.com/library.php?do=view_item&itemid=353" twice

    if you differentiate the RHS, you get an extra 0.8 from the t, and an extra 1/2 from the power, = (0.8/2) :wink:
     
    Last edited by a moderator: Apr 26, 2017
  4. Jul 30, 2011 #3
    Re: Welcome to PF!

    Thanks a lot!:smile: I neglected the 0.8 during the integration. Got it already. Forgotten the basic rule of integration. :frown:
     
    Last edited by a moderator: Apr 26, 2017
  5. May 19, 2013 #4
    may i know from same question as above shown, how to get the -1/60 at the end there?
     
  6. May 19, 2013 #5

    tiny-tim

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    welcome to pf!

    hi mintz! welcome to pf! :smile:
    the ##|^t_0## at the end of the previous line means you have to evaluate it at t and at 0, and subtract :wink:
     
  7. May 19, 2013 #6
    oh~okie~thanks! i made mistake that evaluate at 0 whole things became 0~:frown:
    thanks anyway!=D
     
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