Determine the closed loop transfer functions of the systems shown below:
Standard block diagram algebra.
The Attempt at a Solution
I've moved the take off point such that the diagram now looks like:
I am having difficulty determining G1(s). The solution given is
G1(s) = 4(s + 2) + 1 = 4s + 9
But it is not obvious to me where this is coming from. Taking G1(s) as given, I am able to solve the rest of the question without issue.
Any help appreciated.