Learning Guide Learning Guide

256 • Chapter 6: Examples from Calculuseq2 := d y(t) = −y(t) − x(t)dt> eq3 := diff(z(t),t) = x(t)+y(t)-z(t);eq3 := d z(t) = x(t) + y(t) − z(t)dtThese are two lists of initial conditions.> ini1 := [x(0)=1, y(0)=0, z(0)=2];ini1 := [x(0) = 1, y(0) = 0, z(0) = 2]> ini2 := [x(0)=0, y(0)=2, z(0)=-1];ini2 := [x(0) = 0, y(0) = 2, z(0) = −1]The DEplot3d command plots two solutions to the system of differentialequations {eq1, eq2, eq3}, one solution for each list of initialvalues.> DEplot3d( {eq1, eq2, eq3}, [x(t), y(t), z(t)], t=0..10,> [ini1, ini2], stepsize=0.1, orientation=[-171, 58] );2z2–12y–1–1xDiscontinuous Forcing FunctionsIn many practical instances the forcing function to a system is discontinuous.Maple provides a number of ways in which you can describe asystem in terms of ODEs and include, in a meaningful way, descriptionsof discontinuous forcing functions.