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Lösen von unterbestimmten Gleichungssystemen

AndreasLoibl
1-Newbie

Lösen von unterbestimmten Gleichungssystemen

Hallo,

ich nutze Mathcad 15 Akademisch noch nicht lange und habe ein Problem beim Lösen eines unterbestimmten linearen Gleichungssystems. Ich versuche das Gleichungssystem mit einem Lösungsblock und der Suchen-Funktion herzustellen.

Aber leider funktioniert das ganze nicht. Ich erhalte anstelle der vollständigen Lösung mit Parametern nur eine spezielle Lösung.

Ich habe dieses Beispiel in einem Buch zu Mathcad gefunden und dort funktioniert die Lösung. Ich habe das Beispiel angehängt.

Es wäre schön, wenn mir jemand helfen könnte, weil ich momentan nicht mehr weiter weiß.

Herzlichen Dank,

Andreas Loibl

6 REPLIES 6

You have one equation and three unknowns, so there is an infinite number of possible solutions.

See the attach!

Thanks for your answers.

Untfortunately is my problem not solved, yet.

The right solution from Mathcad should be:

Suchen(x1,x2,x3)->(1-x3-x2,x2,x3)

Mathcad should take x2 and x3 as parameters.

But Mathcad shows only the special-solution vor x2=0 and x3=0: Suchen(x1,x2,x3)->(1,0,0)

I read this example in a handbook of Mathcad, and Mathcad produced there the right solution, that i discribed.

Thanks for your help!

Andreas

The right solution from Mathcad should be:

Suchen(x1,x2,x3)->(1-x3-x2,x2,x3)

Mathcad should take x2 and x3 as parameters.

I read this example in a handbook of Mathcad, and Mathcad produced there the right solution, that i discribed.

Yes, in Mathcad version 13 or earlier, it does give that solution. Versions 13 and earlier used Maple as the symbolic engine. Versions 14 and later use MuPad as the symbolic engine. So I don't think that it's possible to get the answer you want in the current version. Sorry.

Thanks for your answer. I´m very disappointed of Mathcad, because the latest version is worse than the last ones.

Greetings,

Andreas Loibl

the latest version is worse than the last ones.

In some respects, yes, but in others, it's better. MC12 was much worse than MC11, Since then it has got better with every version though, with the exception of the change from Maple to MuPad as the symbolic engine. Even that is not black and white though, the MuPad engine does some things better than the Maple engine. I use both MC11 and MC15, but mostly MC15.

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