2(1-ks (s) 6s2+(5-2k)s+3 R(s)=k(s)=2H1(s)-12(s) 2k(2S2+s+1) 二2 v(s) 6s2+(5-2k)s+3 H(s)= R(s)2k(22+S+1) (s)6s-+(5-2k)s+3( ) 6 (5 2 ) 3 2 (2 1) ( ) ( ) 2 [ ( ) ( )] ( ) 6 (5 2 ) 3 2(1 ) 2 2 1 1 2 2 v s s k s k s s R s k v s k I s I s v s s k s k s s s + − + + + = = = − + − + − = 6 (5 2 ) 3 2 (2 1) ( ) ( ) ( ) 2 2 + − + + + = = s k s k s s v s R s H s s