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## Re: A couple of beginner's questions

 From: Archambault Fabien Subject: Re: A couple of beginner's questions Date: Mon, 25 Feb 2008 08:58:33 +0100 User-agent: Thunderbird 2.0.0.9 (X11/20080213)

```p.numminen a écrit :
```
```Question 1:
How would I command Octave in order to find all the values of x that would
make the functions

f1(x) = 1.035568^x * 1000 - 1000 and
f2(x) = (1.025668^x * 1000 - 1000) * 0.72

equal with each other?
```
I am not sure but if you try to write f1(x)-f2(x) = 0 and solve it with the fsolve function it will work I think. You can see the help at this page : http://octave.sourceforge.net/doc/f/fsolve.html
```
Not really explicit but this function is for nonlinear solving.
```
```
Question 2:
How would I command Octave in order to solve the equation

1.035568^x * 1000 - 1.025668^x * 720 - 280 = 0

?
```
I think also see with fsolve because your equations are nonlinear. Or by hand using the "ln" function...
```
--
Fabien Archambault
Equipe de dynamique des assemblages membranaires
Unité Mixte de Recherches CNRS UHP 7565
Université Henri-Poincaré, Nancy I BP 239,
54506 Vandoeuvre-lès-Nancy, cedex France

Tél : 03.83.68.43.96

```