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From: "Bruno Luong" <b.luong@fogale.findmycountry>
Newsgroups: comp.soft-sys.matlab
Subject: Re: HOw to solve these type of equations
Date: Sun, 5 Aug 2012 08:13:13 +0000 (UTC)
Organization: FOGALE nanotech
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"Dinesh " <revooridinesh@gmail.com> wrote in message <jvkiq9$ipf$1@newscl01ah.mathworks.com>...
>  
> > if no y3' then it not differential equation but algebra like in
> > school. just move the known to the left and unknown to the right to
> > solve and for the first 2 differentials use the matlab od54 functions
> > but need initial conditions
> 
> Thank you for the reply 
> the three equations are functions of y1,y2,y3 and i know the values before time 0-
> 
> my original equations are C1*y1' = F*C2*y2 - C3*y1
> y2' = C4 -B* C5*y3 - C6*y1
> y2-C7=x(t)*y3
>  

From the last equation y3 can be expressed as y2. Your equations is an ODE, that can be solved with ode solvers.

Bruno