解:(1)3(a3﹣a2b+ab2)﹣(6a3+4a2b+3ab2) =3a3﹣3a2b+ab2﹣3a3﹣2a2b﹣ab2 =﹣5a2b; (2)(2x3y)3(﹣7xy2)÷(14x4y3) =8x9y3×(﹣7xy2)÷14x4y3 =﹣56x10y5÷14x4y3 =﹣4x6y2; (3)(m+2n)(2m﹣n) =2m2﹣mn+4mn﹣2n2 =2m2+3mn﹣2n2; (4)(2x﹣y)2 =4x2﹣xy﹣xy+y2 =4x2﹣2xy+y2; (5)899×901+1 =(900﹣1)×(900+1)+1 =810000﹣1+1 =810000. |