Question

(x-y)的平方-(x+y)(x-y)=?

各位，我真的很需要答案，帮帮忙吧！

Answer 1

公因式(x-y)
所以原式=(x-y)[(x-y)-(x+y)]
=-2y(x-y)

Answer 2

(x-y)*(x-y)-(x+y)*(x-y)=(x-y)*[(x-y)-(x+y)]=(x-y)*(-2y)=2y*y-2xy

Answer 3

2y(y-x)