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1-Visitor
July 17, 2017
Solved

Simplifying function taking some variables off.

  • July 17, 2017
  • 2 replies
  • 1690 views

Hi,

 

I'm trying to rewrite function "f"  in the first line of the picture below in terms of only "x2" and "x3":

 

Find f(x2,x3)Find f(x2,x3)

Any ideas ? Is it possible ? Thanks in advance.

 

Att,

 

Ricardo S.

Best answer by Werner_E

As it seems that you tried to use a solve block with "find", here is another approach

Pic.png

2 replies

23-Emerald IV
July 17, 2017

OK:

x1(x2,x3):=x2+x3

f(x2,x3):=x1(x2,x3)+x2+x3

 

Would essentially become: f(x2,x3):=2*x2+2*x3

Then if (also): x2=x1+5*x3, it would mean that x2=x2+x3+5*x3, so 0=6*x3 and x3=0 and finally this means that

f is not a function of x3.

 

Does not make sense.

What exactly do you want?

Success!
Luc

25-Diamond I
July 17, 2017

If both condition have to be considered, as Liuc said, this would mean that x3=0 and x1=x2 and f(x2)=2*x2.

Even with other conditions - if you apply two independend conditions, f would only be dependent on one variable, not on two.

Here are two ways to do it with one condition - not sure if thats waht you are looking for:

Pic.png

 

 

 

 

 

 

Werner_E25-Diamond IAnswer
25-Diamond I
July 17, 2017

As it seems that you tried to use a solve block with "find", here is another approach

Pic.png