伊枫
春芽
共回答了12个问题采纳率:91.7% 举报
1.2a(a-b)-2a平方+3ab
=2a^2-2ab-2a^2+3ab
=ab
2.(a平方b立方-a平方b平方)÷ab平方
=ab-a
3.(a+b)(a平方-ab+b平方)
=a^3-a^2b+ab^2+a^2b-ab^2+b^3
=a^3+b^3
4.(x-y)平方-(y+2x)(y-2x)
=x^2-2xy+y^2-y^2+4x^2
=5x^2-2xy
16.因式分解
1.x立方y立方-2x平方y平方+xy
=xy(x^2y^2-2xy+1)
=xy(xy-1)^2
2.题目应为a(x-y)-b(x-y)+c(x-y)
=(x-y)(a-b+c)
1年前
6