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03-30-2016
03:28 PM

03-30-2016
03:28 PM

What is the reason for this error in the answer?

Basically the answer should be a perfect zero (according to theory and also verified through hand calculation), so why this software is giving such high error.

Please tell me if I am doing something wrong as soon as possible.

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6 REPLIES 6

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03-30-2016
03:38 PM

03-30-2016
03:38 PM

Re: What is the reason for this error in the answer?

Because you are numerically evaluating the integral

The precision with which Mathcad calculates numerical evaluation is in the order of 10^-17.

You're doing nothing wrong. You could set the 'zero tolerance' of numerical calculation to a higher value (e.g. 10^-10) this would show all numbers x with |x|<10^-10 as 0. But it would obscure results that are actually meant to be e.g. 10^-12.

Success!

Luc

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03-30-2016
03:45 PM

03-30-2016
03:45 PM

Re: What is the reason for this error in the answer?

Then what is the solution to this problem, is there any other software with high tolerance value?

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03-30-2016
05:32 PM

03-30-2016
05:32 PM

Re: What is the reason for this error in the answer?

This is not a 'problem'. Just be aware that all calculations go with a certain uncertainty/accuracy.

Simply calculate 1/2-1/3-1/6 and see what comes out.Mathcad will tell you:

MsExcell will tell you 0, until you multiply the result with 10^18, then it spits out 27.76

If you want exact answers, use a symbolic engine (Mathcad, Maple, Mathematica, Maxima).

Success!

Luc

P.S. If you want to know why the 'error' is in the order of 10^-17, have a look at:

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03-30-2016
03:43 PM

03-30-2016
03:43 PM

Re: What is the reason for this error in the answer?

It's numerical evaluation precision error. (10^-17 is a large error?)

Symbolic evaluation gives you zero:

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03-30-2016
03:47 PM

03-30-2016
03:47 PM

Re: What is the reason for this error in the answer?

Yaa..thank bro..drinks on me

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03-30-2016
04:34 PM

03-30-2016
04:34 PM

Re: What is the reason for this error in the answer?

Just change the result formatting from "General" to "Decimal":