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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



