a³-4ab²-a+2b= a(a²-4b²) - (a-2b)= a( a+2b) (a-2b) - (a-2b) = (a²+2ab -1 ) (a-2b) 无量寿佛,佛说苦海无涯回头是岸!施主,我看你骨骼清奇,器宇轩昂,且有慧根,乃是万中无一的武林奇才.潜...