On 04/29/2010 10:06 AM, Alexandre Campos wrote:
> Dear all,
> how can I solve my system, so solve, linsolve,dsolve didn't work ...
> Thanks in advance,
> alexandre
>
> kill(all);
>
> x:
> Xo*%e^(-cita*omega_n*t)*cos(omega_n*(1-cita^2)^(0.5)*t-fio)+X*cos(omega_f*t-fi);
> dx: diff(x,t);
>
> eq1: ev(x, t=0)=0;
> eq2: ev(dx, t=0)=0;
>
> res: solve([eq1,eq2],[Xo,fio]);
>
>
> --
> "No man can serve two masters; for either he will
> hate the one, and love the other; or else he will hold
> to the one, and despise the other. Ye cannot serve
> God and mammon." Matthew 6:24
Transcendental equations cannot usually be solved. Neither can
polynomial equations of degree >=5.
Your best bet is to plot the functions to see where they might have
roots, and to use some numerical scheme such as newton, mnewton, or
find_root.
-sen