3
x1'=x2;
x2'=x1-.2*x2-x1*x1*x1+.3*cos(x3);
x3'=1.0;
x1 = 1.0
x2 = 1.0
x3 = 1.0
x1 = 2.0
x3 = 3.0
x2 = 2.0
x1 = 1.01
x2=1.01
x3=1.001


bt=0
et=88
dt=.1
x1 vs. a