(z+x+y)+(z-x-y) 计算题!

计算（x+y-z)(x-y-z) 计算：(x-y+z)(-x+y+z) 用乘法公式计算(x+y)(x-y)+(-y-z)(-y+z)+(-x+z)(z+x) 计算：（X+y+z)(-x+y+z)(x-y+z)(x+y-z) 计算(x+y+z)(-x+y+z)(x-y+z)(x+y-z) 计算(x+y-z)(z-x-y) ,(x+y-z)(z-x+y) 计算:x^2/(x-y)(x-z)+y^2/(y-x)(y-z)+z^2/(z-x)(z-y) 计算:(y-x)(z-x)/(x-2y+z)(x+y-2z)+(z-y)(x-y)/(x+y-2z)(y+z-2x)+(x-z)(y-z)/(y+z-2x)(x-2y+z) 计算（x-y-z)^2 计算(X+Y+Z)平方 计算(2x+y+z)(2x-y-z), 计算(x+2y-z)(2y+z-x) 计算(x-2y+z)(z-x-2y), (x一2y+z)(-x+2y+z)(计算) 计算:(x+2y-z)(x-2y-z) 计算(x+2y-z)(2y+z-x) 计算：(x-y-z)^2-(x-y+z)^2 (x+2y-z)(x-2y-z)计算过程