foreuler= Eulers metode
rk2, rk4= Runge-Kutta til 2. og 4. orden.
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> f:=(t,x)->1-t-(1/2)*x^2;
> Xe:=dsolve({diff(x(t),t)=f(x(t),t), x(0)=0}, x(t), type=numeric,
> method=classical[foreuler], stepsize=0.1);
> Xe(0.2);
> Xrk2:=dsolve({diff(x(t),t)=f(x(t),t), x(0)=0}, x(t), type=numeric,
> method=classical[rk2], stepsize=0.1);
> Xrk2(0.2);
> Xrk4:=dsolve({diff(x(t),t)=f(x(t),t), x(0)=0}, x(t), type=numeric,
> method=classical[rk4], stepsize=0.1);
> Xrk4(0.2);
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