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Every so often, MAthcad 15 surprises me!

-MFra-
21-Topaz II

Every so often, MAthcad 15 surprises me!

Every so often, MAthcad 15 surprises me!

curiosity.jpg

1 ACCEPTED SOLUTION

Accepted Solutions
LucMeekes
23-Emerald III
(To:-MFra-)

Mathcad 11 / Maple:

LM_20190113_Mathcad 15.png

Luc

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5 REPLIES 5
LucMeekes
23-Emerald III
(To:-MFra-)

Mathcad 11 / Maple:

LM_20190113_Mathcad 15.png

Luc

Looks like Maple in MC11 ignores the possibility of a being zero. In this case the result of Maple in MC11 is wrong!

 

B.png

 

Admittedly MC15's answer without this specific "assume" is wrong in the same sense, too 🙂

 

LucMeekes
23-Emerald III
(To:Werner_E)

Maybe it's not so wrong...

LM_20190113_Mathcad 151.png

 

Note that the taylor-series of exp(a*x) is 1+ a*x+a^2*x^2/2+...

so in (exp(a*x)-1)/a, the 1 is subtracted out by -1,the next term divided by a leaves x, and the following terms all become 0 when a=0.

Luc


@LucMeekes wrote:

Maybe it's not so wrong...

 



Not so, yes, but its still problematic to write a division by "a" without stating that "a" does not equal zero.

I would have expected to see some kind of if-statement as we see it from Mathcad/muPAd/Maple on many other occasions, too.

 

So again we learn that Mathcad and its symbolics by far is not perfect - not even MC11 & Maple 😉

B1.png

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