Date: Jan 31, 2013 8:45 PM
Author: Louis Talman
Subject: Re: steady state concetration
On Wed, 30 Jan 2013 20:05:12 -0700, jeremy <j.witoslawska@gmail.com> wrote:

> Hi,

> i'm new in Mathematica and i've a project to do. i've to find at what

> time 90% of the steady state concetration of C is achieved. and soo far

> i have something like that, for 3 different k values:

>

> With[{k = 0.3}, eqn1s = 0 == k (1/2 - z[t]) (1/3 - z[t])];

> With[{k = 0.6}, eqn2s = 0 == k (1/2 - z[t]) (1/3 - z[t])];

> With[{k = 0.9}, eqn3s = 0 == k (1/2 - z[t]) (1/3 - z[t])];

> Evalute[{eqn1s, eqn2s, eqn3s}]

> NSolve[Evaluate[{eqn1s, eqn2s, eqn3s}], z[t]]

>

> and what i get in NSolve is supposedly be the steady state, but i don't

> know how to find this 90% and my profesor told me that i could try do

> this with DSolve, but something doesn't work. i hope that someone will

> be able to help me with this.

>

> Thanks

>

The purpose of this list isn't that of solving people's homework problems

for them.

If your professor wanted someone to tell you how to work the problem,

don't you think *he* would've told you how to work it?

--

--Louis A. Talman

Department of Mathematical and Computer Sciences

Metropolitan State University of Denver

<http://rowdy.msudenver.edu/~talmanl>