(x+y+z)(x-y-z)={x+(y+z)}{x-(y+z)} 根据(A+B)(A-B)=A^ -B^ 则 (x+y+z)(x-y-z)={x+(y+z)}{x-(y+z)}=X^-(y+z)^如果还要化简,直接展开来就可以了
麻烦采纳,谢谢!