(x-y+z)(x+y-z)-(y-z-x)(y+z-x)
为啥*(1-2)
追答(-2)的100次方
=(-2)的99次方x(-2)
(x-y+z)(x+y-z)-(y-z-x)(y+z-x)
追答(x-y+z)(x+y-z)-(y-z-x)(y+z-x)
追问答这题加200分
追答(x-y+z)(x+y-z)-(y-z-x)(y+z-x)
=[x-(y-z)][x+(y-z)]-[(y-x)-z][(y-x)+z]
=x²-(y-z)²-[(y-x)²-z²]
=x²-y²+2yz-z²-(y²-2xy+x²-z²)
=x²-y²+2yz-z²-y²+2xy-x²+z²
=-2y²+2yz+2xy
=-2y(y-z-z)