The signal flow graph of a system is shown below. $U(s)$ is the input and $C(s)$ is the output.
Assuming, $h_1=b_1$ and $h_0=b_0-b_1a_1$ , the input-output transfer function, $G(s)=\dfrac{C(s)}{U(s)}$ of the system is given by
- $G(s)=\dfrac{b_0s+b_1}{s^2+a_0s+a_1} \\ $
- $G(s)=\dfrac{a_1s+a_0}{s^2+b_1s+b_0} \\ $
- $G(s)=\dfrac{b_1s+b_0}{s^2+a_1s+a_0} \\$
- $G(s)=\dfrac{a_0s+a1}{s^2+b_0s+b_1}$