化简求职:(2x-y+3z)(-2x-y-3z)-(x+2y-3z)²
化简求值:(2x-y+3z)(-2x-y-3z)-(x+2y-3z)²
化简求值:(2x-y+3z)(-2x-y-3z)-(x+2y-3z)²,其中x=1,y=-1,z=1