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04-04-2016
08:48 AM

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04-04-2016
08:48 AM

"simple" derivation

Hi,

I’m trying a simple derivation with mathcad 15. At least I thought it was easy.

The function is

I want Mathcad to calculate

But the outcome is obviously missing a term…

Check the attachment for the corresponding xmcd or png.

Can somebody tell me what’s wrong?

Michael

Solved! Go to Solution.

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04-04-2016
09:58 AM

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04-04-2016
09:58 AM

> Can somebody tell me what’s wrong?

Yes, Mathcad is often very (too) tolerant in this respect, but its wrong from a mathematical point of view to use the same variable for limit AND integration variable as you had done. Use different variables and all works OK.

Mathcads behavior nevertheless is wrong - it should throw an error message instead of yielding a wrong result.

WE

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04-04-2016
09:58 AM

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04-04-2016
09:58 AM

> Can somebody tell me what’s wrong?

Yes, Mathcad is often very (too) tolerant in this respect, but its wrong from a mathematical point of view to use the same variable for limit AND integration variable as you had done. Use different variables and all works OK.

Mathcads behavior nevertheless is wrong - it should throw an error message instead of yielding a wrong result.

WE

04-05-2016
04:57 AM

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04-05-2016
04:57 AM

Thank you for the quick (and good) answer!