题目

1 -x^3y^3+2x^2y^2-xy
2 4x^2-(x^2+1)^2
3 3x^2-3x+四分之三
4 16x^4-y^4
5 8(a-b)^2-12(b-a)
6 25(m-n)^2-9(m+n)^2
这个是^次方的意思

提问时间：2021-02-05

答案

1.-x^3y^3+2x^2y^2-xy=-xy(x^2y^2-2xy+1)=-xy[(xy)^2-2xy+1]-xy(xy-1)^22.4x^2-(x^2+1)^2=(2x)^2-(x^2+1)^2=(2x+x^2+1)(2x-x^2-1)=-(x+1)^2(x^2-2x+1)=-(x+1)^2(x-1)^23.3x^2-3x+3/4=3(x^2-x+1/4)=3(x-1/2)^24.16x^4...