例 r()+3(t)+2r(t)=e(t) 2r(t)=2Ae 3r'(t)=3A(j)e1 + r"(t)=A(/o)2e1 可求出A ALOjO)+3(o)+2]eo=e 特解 V0) rlt H( Jor Q r(t) (0)2+3(0)+2 j0)2+3()+29 例： ( ) 3 ( ) 2 ( ) ( ) " ' r t + r t + r t = e t j t j t j t r t A j e r t A j e r t Ae      2 "( ) ( ) 3 '( ) 3 ( ) 2 ( ) 2 = = = j t j t A j j e e   [( ) +3( ) + 2] = 2 ( ) 3( ) 2 ( ) 2 + + =    j j e r t j t ( ) 3( ) 2 ( ) 1 ( ) 2 + + = =     e j j r t H j j t 可求出A 特解