因式分解:(x+y)(x+y+2xy)+(xy+1)(xy-1)=_.
问题描述:
因式分解:(x+y)(x+y+2xy)+(xy+1)(xy-1)=______.
答
(x+y)(x+y+2xy)+(xy+1)(xy-1)
=(x+y)2+2xy(x+y)+x2y2-1
=(x+y+xy)2-1
=(x+y+xy+1)(x+y+xy-1).
故答案为(x+y+xy+1)(x+y+xy-1).