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Integral with a twist

  1. Apr 6, 2010 #1
    How can the following integral be approached?
    \int f(t) \sqrt{dt}

    thanks in advance.
  2. jcsd
  3. Apr 6, 2010 #2

    Ben Niehoff

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    I'm pretty sure it's meaningless. The units don't work out.

    However, it would make sense to write something like

    [tex]\int_C f(x,y) \sqrt{dx^2 + dy^2}[/tex]

    where C is some contour.
  4. Apr 7, 2010 #3
    There was a long argument about this in one of the forums a few months ago. But Apteronotus will have to give us a context before we can say anything about it.
  5. Apr 9, 2010 #4
    It doesn't make sense. Since [tex]\sqrt{x+dx} = \sqrt{x} + \frac{dx}{2\sqrt{x}}[/tex], it follows that [tex]\sqrt{dx} = dx/0[/tex], which is of course meaningless.
  6. Apr 9, 2010 #5
    Do you have a link to this thread? I'd be interested in reading it.
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