x^2+y^2-x^2y^2-4xy-1分解因式
问题描述:
x^2+y^2-x^2y^2-4xy-1分解因式
答
x^2+y^2-x^2y^2-4xy-1
=(x^2+y^2-2xy)-(x^2y^2+2xy+1)
=(x-y)^2-(xy+1)^2
=(x-y+xy+1)(x-y-xy-1)