(1)解Ly=f 得 f-l·y( 1 ) 解Ly = f ÷÷÷÷÷÷øö ççççççèæ n nffff l l l O M O 321 3 2 1 1 1 1 ( L , f ) =1 1 y = f - 1 = - × i i i i y f l y { i = 2 , 3 , L , n 得 --------(7)