(4)求Lte [te]=l te e p dt=l te -(p-s)t Re p> re s (P-s) 同理 LIt"e= (P-s) (5)求L()“(p)2r Ctf(tedi D[() dlff(t) L[tf()=(-1 dlff(t](4) 求 [ ] st L te . ( ) 1 [ ] 2 0 0 ( ) p s t e t e e dt t e dt s t s t p t p s t − =  = =     − − − L Re P  Re s 同理 . ( ) ! [ ] n n st p s n t e − L = (5) 求 L[tf (t)]   − = − 0 ( ) ( ) , ( ) t f t e dt dp df p pt . [ ( )] [ ( )] dp d f t tf t L L = − . [ ( )] [ ( )] ( 1) n n n n dp d f t t f t L L = −