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Homework Help: I know this might be easy but i forgot how to solve please help

  1. Dec 1, 2007 #1
    Please help me..

    integrate this

    [tex]\int[/tex][tex]\frac{1}{U\sqrt{1-U^2}}dU[/tex]
     
  2. jcsd
  3. Dec 1, 2007 #2

    rock.freak667

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    ..Try using integration by parts and see if you can solve

    u=[itex]\frac{1}{U}[/itex] find du/dx
    [itex]\frac{dv}{dx}=\frac{1}{\sqrt{1-U^2}}[/itex] so get v=

    and

    [tex]\int u\frac{dv}{dx}dx=uv-\int v\frac{du}{dx}dx[/tex]
     
  4. Dec 1, 2007 #3

    Dick

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    It can be done straightforwardly with a trig substitution, like u=sin(t).
     
  5. Dec 1, 2007 #4
    Sorry but...

    the original question wasintegration from [tex]\epsilon[/tex]to[tex]\pi-\epsilon[/tex]
    [tex]\int[/tex][tex]\frac{1}{sinx}dx[/tex]

    I tried to integrate it straight but i don't know how calculate cosec and cot...
     
    Last edited: Dec 1, 2007
  6. Dec 2, 2007 #5

    Avodyne

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    Try the substitution u = tan(x/2).
     
  7. Dec 2, 2007 #6
    :)thanks guys. I got it~
     
  8. Dec 13, 2007 #7
    What is the term for the slope on an x axis that runs parallel but never actually touches the x axis?
     
  9. Dec 13, 2007 #8

    Dick

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    Get your own thread. But until you do 'horizontal asymptote with y value 0'.
     
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