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Topic: Double integration
Replies: 10   Last Post: Dec 6, 2011 12:42 PM

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 Marcio Barbalho Posts: 15 Registered: 6/2/10
Re: Double integration
Posted: Dec 3, 2011 9:03 PM

"Roger Stafford" wrote in message <jbei9d\$feq\$1@newscl01ah.mathworks.com>...
> "Marcio Barbalho" <marciobarbalho@live.com> wrote in message <jbb6bl\$6af\$1@newscl01ah.mathworks.com>...
> > Apparent the result of the original double integration is 53.22. I would like to prove it.
> - - - - - - - - -
> Marcio, I got around to applying those techniques I have described to you earlier in this thread and arrived at a somewhat higher value than the 53.22 you quoted. My answer was 53.573533745 . How did you arrive at your value?
>
> As I stated, there is a closed form for the inner integral using polar coordinates, and the outer integral was done numerically using one of matlab's quadrature routines with the inner integral formula as an integrand.
>
> Roger Stafford

Very nice! I shall give it another go tomorrow. I got 53.22 using a calculator. No tricks, just typed the original double integral and got the result 2 min later. I set the calculator to work with 2 decimal places, otherwise it would take much longer to get to a 'better' result (like yours).

Thank you

Date Subject Author
12/1/11 Marcio
12/1/11 Roger Stafford
12/1/11 Roger Stafford
12/2/11 Marcio Barbalho
12/2/11 Roger Stafford
12/2/11 Marcio Barbalho
12/2/11 Roger Stafford
12/4/11 Steven Lord
12/6/11 Roger Stafford
12/3/11 Roger Stafford
12/3/11 Marcio Barbalho