3
x1' = 10*(-x1+x2);
x2' = 28*x1-x2-x1*x3;
x3' = -2.67*x3+x1*x2;
x1 = 1
x2 = 1
x3 = 1
x3 = 1.001
x2 = 1.001
x1 = 1.001
bt = 0
et = 30 
dt = .01
x2 vs. x3