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Alex Palau
03/20/05 3:14pm

Hi,

I'm quit new using Mathematica and I have a problem with following NIntegrate function:

NIntegrate[V/(F*k2)*((2*g*Ho*(x - ra)^((1 + n)/n) )/(x + ra))^(-n), {x, rmf, rmi}]

(see attach file)

I will not get into details on the meaning of the values but they are constant, except for 'x'. NIntegral seems that works fine but I found a situation where I got 652.13 as result when Ho=3.92. I knew that this was not the right result. I repeated the calculation with Ho=4 and result was closer to the expected result. After that I repeated the calculation using Ho=3.92 back again. Result at this time was 540.29 (the right result). My question is how can I get different results with same initial values using NIntegral? How can I be sure of the result of NIntegrate? How shall I use this function properly?

Best regards

Alex

Attachment: ISOMixing.nb, URL: ,

Subject (listing for 'NIntegral function')
Author Date Posted
NIntegral function Alex Palau 03/20/05 3:14pm
Re: NIntegral function yehuda ben-s... 03/23/05 4:56pm
Re: NIntegral function Alex Palau 03/29/05 02:30am
Re: NIntegral function yehuda ben-s... 04/03/05 01:10am
Re: NIntegral function yehuda ben-s... 04/04/05 2:52pm
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