自动控制原理（双语教学）：4.6.5.1

Solution 4.6.5.1 Wemust have ~ G 1+ ~ G = G 1+GH Cross-multiplying weobtain ~ G(1 + GH)=G(1+ ~ G;; or ~ G(1+ GH)=G + G ~ G: Collecting terms in ~ G wethenhave ~ G(1;G+ GH)=G;; or ~ G = G 1+G(H ;1) : 1