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Topic: Solving equation
Replies: 3   Last Post: Apr 7, 2008 12:10 PM

 Messages: [ Previous | Next ]
 Wouter Geelen Posts: 9 Registered: 3/29/08
Re: Solving equation
Posted: Apr 4, 2008 6:37 PM

roberson@ibd.nrc-cnrc.gc.ca (Walter Roberson) wrote in
message <ft694d\$5ki\$1@canopus.cc.umanitoba.ca>...
> In article <ft67km\$agj\$1@fred.mathworks.com>,
> Wouter Geelen <wouser_geelen@hotmail.com> wrote:
>

> >I tried to do this myself but I can't get it done. I got
> >the following equation.

>
> >Ti = -1200*exp(-1/7200*t)+1200
>
> >Now I want to solve this function for Ti = 1080. So what
I
> >want to find is t. How do I do that :?
>
> Ti = -1200*exp(-1/7200*t)+1200, so
> Ti - 1200 = -1200 * exp(-t/7200), so
> (1200 - Ti)/1200 = exp(-t/7200), so
> ln((1200 - Ti)/1200) = -t/7200, so
> -ln(1200/(1200-Ti)) = -t/7200, so
> t = 7200 * ln(1200/(1200-Ti))
>
> Substituting in Ti = 1080, we get the result 7200 * ln(10)
>
> --
> "Is there any thing whereof it may be said, See, this

is new? It hath
> been already of old time, which was before us." --
Ecclesiastes

Hahahaha yeah I know it can be done by algabra I already
did myself lol but how do I this in matlab? Ain't there a
function solve equation for paramater x?!? Or something
like maple has?

Date Subject Author
4/4/08 Wouter Geelen
4/4/08 Walter Roberson
4/4/08 Wouter Geelen
4/7/08 Loren Shure