x^2－2xy－2y^2 因式分解
问题描述：
x^2－2xy－2y^2 因式分解
答
x^2-2xy-2y^2=x^2-2xy+y^2-3y^2
=(x-y)^2-3y^2
=(x-y+3y)(x-y-3y)
=(x+2y)(x-4y)
答
原式＝（x-y)^2-3y^2
＝(x-y+根号3y)(x-y-根号3y)
答
(x-y)^2-3y^2
=(x-y-√3 y)(x-y+√3 y)