(a) Consider a single loop system of the configuration shown in Figure P16.2.27 (a) with positive feedback. Although positive feedback generally results in instability, it is frequently employed at low magnitudes or in portions of a large control system, particularly in an inner loop. Obtain an expression for C(s)/R(s).
(b) Figure P16.2.27 (b) illustrates a multiple-loop feedback control system, where the argument s is omitted for simplicity. Reduce it to a single-loop configuration.
