Question

(x+y)的二次方(x-y)+(x+y)(x-y)的二次方

用提取公因式 做
(x+y)的二次方乘以(x-y) + (x+y）乘以(x-y)的二次方

Answer 1

(x+y)的二次方(x-y)+(x+y)(x-y)的二次方
=(x+y)(x-y)(x+y+x-y)
=2x*(x+y)(x-y)

Answer 2

自己想