M

<b>H(s) = 1/(s*(s+2))</b>

I think the system is marginally stable because of the pole at origin. But when I plot the step response in MATLAB I get a linear line which keeps on increasing that makes me think that system is unstable. Link for step response is given below:

http://postimg.org/image/rg9422r0t/

Any help would be appreciated.