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Calc two help please

  1. Feb 8, 2005 #1
    Calc two help please :(

    Ok, I have the following two problems:

    [tex] \frac{d}{dx} \ \int_0^1 \ e^{tan^-1(t)} \ dt \\\\
    [/tex]

    and

    [tex]
    \int \ \frac{Sin[x]}{1+x^2} \ dx

    [/tex]

    I have tried to do substitution on both and integration by parts on the second one but nothing seems to work. If I could just get some pointers in the right direction on where to start that would be awesome, thanks a lot.
     
    Last edited: Feb 8, 2005
  2. jcsd
  3. Feb 8, 2005 #2

    dextercioby

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    1.Are you sure about the first...?In the form posted,it's zero...
    2.It's not an integral solvable in the "family" of "elementary"functions.

    Daniel.
     
  4. Feb 8, 2005 #3
    1. I am not sure why its 0, but that is the form the problem is in and 0 is what I got when I did it in Mathematica. I am not really sure on how to go about evaluating it though as if I do U substitution I get x in my denominator.

    2.If it makes any difference it is actually an definite integral with lower limit -1 and upper limit 1. I don't think that should make a difference however.

    Thanks for the help.
     
    Last edited: Feb 8, 2005
  5. Feb 8, 2005 #4

    dextercioby

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    OMG,for #2,it MAKES A HUGE DIFFERENCE...The integral is zero for symmetry reasons...

    1.the first integral,in the form u posted is a number.The derivative of a number wrt any variable (x,y,z,t,...) is IDENTICALLY ZERO.

    Daniel.
     
  6. Feb 8, 2005 #5
    Thanks a lot!
     
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