Récupérer une solution d.une équation pour en faire une variable

waricl shared this question 2 weeks ago
Answered

Bonjour. Est ce possible de récupérer la solution d.une équation {x=3} par exemple quand cette solution dépends d’autre paramètres. Quelle est la commande á utiliser.

Comments (4)

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Bonjour ,

est-ce que la commande liste = Racines( <Fonction>, <x min>, <x max> ) ne ferait pas l'affaire

Cordialement

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Bonjour. MembreDroite (<équation>)

Exemple

a est un curseur

MembreDroite(2x+1=a) (cela crée une fonction b(x,y))

c=b(2,4) (dans c, tu as ta solution (tu peux mettre n'importe quels nombres à la place de 2 et 4...))

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It depends a lot on the context.

Example: GeoGebra v.5 or 6 Classic - CAS View.

In line 1 you solve an equation using the Solutions command, then you get a single value.

In line 2 you enter a function f(x)


If you want to evaluate the function at the solution point which you got in line 1, type:


f($1)


Basically, you can use $1 as if it was a user defined value. (I've used command Solutions instead of Solve, so the list of values doesn't contain the name of the variable)


If in line 1 you get a list containing more values, you can assign a variable to each one of them, e.g.


a:=Element($1,2)


creates the variable a having as value the second solution listed in CAS line 1.

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If you are using the CAS Calculator app, you can assign a label to the objects in CAS View, and use these labels as values for further calculations.


Please see https://www.geogebra.org/m/... for some interactive examples

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