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Hard integral

  • Thread starter dirk_mec1
  • Start date
  • #26
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But I wonder Dick how did you actually find this way of solving this particular integral? I know the "differentiation under the integral sign" trick but as you've found out those tan and sec made it hard to see if it's actually working so I immediately went looking for another way (and failed...).
 
  • #27
Dick
Science Advisor
Homework Helper
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You solve it by solving it. Gotta admit, I do cheat a bit. I messed around a bit with parametrizing it. Settled on exp(-a*sec(x)^2) as the most plausible. Then I used Maxima (a free computer algebra system) to try and integrate the results. It popped out really fast. Then I had to go back and figure out how Maxima arrived at the results it did. That was the hard part. Then I explained to to you. There. You know my trade secrets.
 

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