C(s)100(4s+1) 2-11 E(s)10(12s2+23s+5) R(s)12s2+23s+25 RO 12s2+23s+25 2-12( (s) R (R1C1S+1)(RCS+10) =R,①.C+D)(b)U() R. CS (b) U(s)R1(R2C2S+1) ;(s)R。(R1+R2)C2S+1 2-13 RR RoR,CCS+rcas+R,R 2-14 Q K I s+1 a(s) TmS+ △u u 2-15 32 s(TmS+1) 11 3126 (s) TmS"+(1+3k3k, km)s+31.26k3k（2-11题~2-15题） 2-11 12s 23s 25 100(4s 1) R(s) C(s) 2 + + + = 12s 23s 25 10(12s 23s 5) R(s) E(s) 2 2 + + + + = 2-12(a) R C s (R C s 1)(R C s 10) U (s) U (s) o 1 1 1 o o i o + + = − (R C s 1) (b) R R U (s) U (s) o o o 1 i o = − + (b) (R R )C s 1 (R C s 1) R R U (s) U (s) 1 2 2 2 2 o 1 i o + + + = − 2-13 2 1 2 3 o 2 1 1 2 3 o 1 2 i o R R C C s R C s R R R R U (s) U (s) + + = − 2-14 T s 1 K U (s) (s) m 1 a m + =  T s 1 K M (s) (s) m 2 a m + = −  2-15 11 1 3 2 k3 s(T s 1) k m m + 3 k st 11 1 i o ui uo u u1 u2 ua ut 3 t m 3 m 2 i m o T s (1 3k k k )s 31.26k k 31.26 (s) (s) + + + =  