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Calculate integral

  1. Feb 14, 2009 #1
    I have some problem with following integral. In attachment a pdf with integral..
    I have done a integration by sobstitution but i have not a result ....
    Tank for your in interest
    best regards
     

    Attached Files:

  2. jcsd
  3. Feb 14, 2009 #2

    tiny-tim

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    why couldn't you type that out? :frown:

    try substituting so that sin becomes cos of something else.
     
  4. Feb 15, 2009 #3
    Ok...
    I have done this question because the calculate on site "wolfram mathematica online integrator" only indefinite integral is very complicated and i don't understand as i can obtain this....
    Cataldo...
     

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  5. Feb 15, 2009 #4

    mathman

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    By a little manipulation you can transform it into an integral from 0 to 1 of the following:

    2[(1+x)1/2 + [(1-x)1/2]/(1-x2). Essentially this was done by collapsing the integral into 0 to pi/2 and then letting x=sin.

    See if you can go further.
     
  6. Feb 16, 2009 #5
    Ok...Tanks mathman
    Is exactly x=sin and integral from 0 to 1.. but i obtain [(1+x)^(1/2)]/(1-x^2)... Does it correct?
     
  7. Feb 16, 2009 #6

    tiny-tim

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    how about sinx = cos(π/2 - x)? :wink:
     
  8. Feb 16, 2009 #7

    mathman

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    The sin is positive from 0 to pi and negative from pi to 2pi. I first collapsed the second interval into the first, so I had two terms: 1+sin and 1-sin. Next collapsing to 0 to pi/2 with a factor of 2. Finally let x=sin.
     
  9. Feb 17, 2009 #8
    Hi nathaman..Tanks for your replay
    I understand your method but the software mathematica can not assess the definte integral because the fuction between 0 to 1 not converge...exist the indefinte integral indeed mathematica assess it... I think that is necessary assess it by numerical integration...
     
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