8m4n的精选

问题详情：计算(－8m4n＋12m3n2－4m2n3)÷(－4m2n)的结果等于()．A．2m2n－3mn＋n2            B．2m2－3mn2＋n2C．2m2－3mn＋n2                 D．2m2－3mn＋n【回答】C点拨：原式＝8m4n÷4m2n－12m3n2÷4m2n＋4m2n3÷4m2n＝2m2－3mn...