(x+y+z)^2-(x-y-z)^2因式分解
问题描述：
(x+y+z)^2-(x-y-z)^2因式分解
答
(x+y+z)^2-(x-y-z)^2=
(x+y+z+x-y-z)(x+y+z-x+y+z)=2x(2y+2z)=4x(y+z)=4xy+4xz