- [35] Investigate the stability of the following systems (it is recommended you check your results using Matlab's pz map.m) H(s)=\frac{s+2}{\left(s^{2}-5 s-6\right)} H(s)=\frac{s+2}{\left(s^{2}+9\right)} H(s)=\frac{s^{2}+6}{\left(s^{2}+5 s+4\right)} h(t)=e^{-t} \sin (4 t) \text

{ for the case where } t \geq 0 \frac{d^{2} y}{d t^{2}}-3 \frac{d y}{d t}+2 y=\frac{d x}{d t}-x \frac{d^{2} y}{d t^{2}}+3 \frac{d y}{d t}+2 y=\frac{d x}{d t}+x \frac{d^{2} y}{d t^{2}}+\frac{d y}{d t}-2 y=\frac{d x}{d t}-x