I have a basic question from ogata. i hope you know the answer.

consider the system defined by matrices: A=[0 1 0; 0 0 1;
-6 -11 -6]
B=[0;
0;
1]
C=[c1 c2 c3]

Except for the obvious choice of c1ÂÃ, find an example set of c1, c2, c3 that will make the system unobservable??

To check the observability, i have formed observ.matrix Obsv=[C; CA; CA^2] the determinant of the "Obsv" must be nonzero. and it must be full rank. When i formed the "Obsv" matrix, such complicated matrix was become. Do you have any suggestions for c1, c2 and c3? Thank you

consider the system defined by matrices: A=[0 1 0; 0 0 1;

Except for the obvious choice of c1ÂÃ, find an example set of c1, c2, c3 that will make the system unobservable??

To check the observability, i have formed observ.matrix Obsv=[C; CA; CA^2] the determinant of the "Obsv" must be nonzero. and it must be full rank. When i formed the "Obsv" matrix, such complicated matrix was become. Do you have any suggestions for c1, c2 and c3? Thank you