1.(x+3)(x-3)-(x+3)^2-(x+3)^2 2.(3m-2)(m-3)-3(m^2
问题描述：
1.(x+3)(x-3)-(x+3)^2-(x+3)^2 2.(3m-2)(m-3)-3(m^2
1.(x+3)(x-3)-(x+3)^2-(x+3)^2 2.(3m-2)(m-3)-3(m^2-7m+9),其中m=-2又1/2
答
(x+3)(x-3)-(x+3)^2-(x-3)^2=x^2-9-x^2-6x-9-x^2+6x-9=6x-x^2-27(3m-2)(m-3)-3(m^2-7m+9)=3m^2-11m+6-3m^2+7m-27=-4m-21=-4x(-2.5)-21=10-21=-11在我回答的右上角点击【评价】,然后就可以选择【满意,问题已经完美解...