Hi Peter,

I'm back again. I have been working away at control theory and am happy with my understanding.

I used Matlab to convert my laplace transform to a z transform.
0.00375
X= ---------------------
(s+0.15)*(s+0.25)

Which converts it to

0.000438*z + 0.000410 -------------------------- z^2-1.81*z+0.818

then the difference equation is got by dividing the num and dem them by the highest order z

0.000438 + 0.000410z^-1 ----------------------------- 1-1.81*z^-1+0.818*z^-2

therefore

x(n)-1.81

therefore

x(n) = 1.81

Which is a little different to your result of

x(n) = 1.81

Have I got lost somewhere again?

I'm back again. I have been working away at control theory and am happy with my understanding.

I used Matlab to convert my laplace transform to a z transform.

Which converts it to

0.000438*z + 0.000410 -------------------------- z^2-1.81*z+0.818

then the difference equation is got by dividing the num and dem them by the highest order z

0.000438 + 0.000410z^-1 ----------------------------- 1-1.81*z^-1+0.818*z^-2

therefore

x(n)-1.81

***x(n-1)+0.818***x(n-2) = 0.000438***u(n)+0.0004104***u(n-1)therefore

x(n) = 1.81

***x(n-1)-0.818***x(n-2) +0.000438***u(n)+0.0004104***u(n-1)Which is a little different to your result of

x(n) = 1.81

***x(n-1)-.819***x(n-2)+.0004387***u(n-1)+.0004104***x(n-2)Have I got lost somewhere again?