% exa1-40_differential_equation.m for example 1-40
% differential equation

clear all;
A=[0 1; -39.478 0];
B=[0;1];
C=[1,0];
D=[0];
v0=[2;0];
t=0:0.01:4;
x=[0*ones(size(t))]';
[y,v]=lsim(A,B,C,D,x,t,v0);
plot(t,y)