快答因式分解
(x^2+y^2-1)^2-4x^2y^2
参考答案:(x^2+y^2-1)^2-4x^2y^2
=(x^2+y^2-1-2xy)(x^2+y^2-1+2xy)
=((x-y)^2-1)((x+y)^2-1)
=(x-y-1)(x-y+1)(x+y-1)(x+y+1)
(x^2+y^2-1)^2-4x^2y^2
参考答案:(x^2+y^2-1)^2-4x^2y^2
=(x^2+y^2-1-2xy)(x^2+y^2-1+2xy)
=((x-y)^2-1)((x+y)^2-1)
=(x-y-1)(x-y+1)(x+y-1)(x+y+1)