x^4+y^4+1+8xyz-2(y^2z^2+z^2x^2+x^2y^2+x^2+y^2+z^2)

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x^4+y^4+1+8xyz-2(y^2z^2+z^2x^2+x^2y^2+x^2+y^2+z^2)
x^4+y^4+1+8xyz-2(y^2z^2+z^2x^2+x^2y^2+x^2+y^2+z^2)

x^4+y^4+1+8xyz-2(y^2z^2+z^2x^2+x^2y^2+x^2+y^2+z^2)
x^4+y^4+z^4+1+8xyz-2(y^2z^2+z^2x^2+x^2y^2+x^2+y^2+z^2）
=（x^2+y^2)+(z^2+1)^2+8xyz-4x^2y^2-2x^2z^2-2y^2z^2-2x^2-2y^2-4z^2
=（x^2+y^2)+(z^2+1)^2+8xyz-2z^2(x^2+y^2)-2(x^2+y^2)-4x^2y^2-4z^2
=（x^2+y^2)+(z^2+1)^2-2(z^2+1)(x^2+y^2)+4(2xyz-x^2y^2-z^2)
=[(x^2+y^2)-(z^2+1)]^2-[2(xy-z)]^2
=(x^2+y^2-z^2-1+2xy-2z)(x^2+y^2-z^2-1-2xy+2z)

x^4+y^4+z^4+1+8xyz-2(y^2z^2+z^2x^2+x^2y^2+x^2+y^2+z^2）
=（x^2+y^2)^2+(z^2+1)^2+8xyz-4x^2y^2-2x^2z^2-2y^2z^2-2x^2-2y^2-4z^2
=（x^2+y^2)^2+(z^2+1)^2+8xyz-2z^2(x^2+y^2)-2(x^2+y^2)-4x^2y^2-4z^2
...

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x^4+y^4+z^4+1+8xyz-2(y^2z^2+z^2x^2+x^2y^2+x^2+y^2+z^2）
=（x^2+y^2)^2+(z^2+1)^2+8xyz-4x^2y^2-2x^2z^2-2y^2z^2-2x^2-2y^2-4z^2
=（x^2+y^2)^2+(z^2+1)^2+8xyz-2z^2(x^2+y^2)-2(x^2+y^2)-4x^2y^2-4z^2
=（x^2+y^2)^2+(z^2+1)^2-2(z^2+1)(x^2+y^2)+4(2xyz-x^2y^2-z^2)
=[(x^2+y^2)-(z^2+1)]^2-[2(xy-z)]^2
=(x^2+y^2-z^2-1+2xy-2z)(x^2+y^2-z^2-1-2xy+2z)
=[(x-y)^2-(z-1)^2][(x+y)^2-(z+1)^2]
=(x-y-z+1)(x-y+z-1)(x+y-z-1)(x+y+z+1)

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2x+3y+4z,xyz (x*x+2)(y*y+4)(z*z+8)=64xyz,求x,y,z xyz-【2xy-（3xyz-yz）+4xyz】,其中x=2,y=-1/2,z=-1 xyz-【2xy-（3xyz-yz）+4xyz】,其中x=2,y=-1/2,z=-1 (X^+2)(Y^+4)(Z^+8)=64XYZ 3x^2y-{xyz-（2xyz-x^2z）-4x^2z+[3x^2y-(4xyz-5x^z-3xyz)]}化简 x^2y--[-x^2y-(2XYZ-X^2Z-3x^2y)-4x^2z]-XYZ其中x=-3,y=2,z=-1x^2y--[-x^2y-(2XYZ-X^2Z-3x^2y)-4x^2z]-XYZ其中x=-3,y=2,z=-1 3x^2y-[2x^2y-(2xyz-x^2z)-4x^2z]-xyz ,其中x=-2,y=-3,z=1 3x²y-[2x²y-(2xyz-x²z)-4x²z]-xyz,其中x=-2 y=-3 z=1 3x²y-[2xyz-(2xyz-x²yz)+3x²y],其中x=-4,y=1/2,z=3 x^4+y^4+1+8xyz-2(y^2z^2+z^2x^2+x^2y^2+x^2+y^2+z^2) 方程组X:Y:Z=4:7:8,X+Y+2Z=54 求XYZ 化简3X^2y-{xyz-(2xyz-9x^2z+4x^2z)+[3x^2y+(4xyz-5x^2z-3xyz)]}等于（）A 2xyz-2x^2z B 6x^2y-4xyz+2x^2zC 6x^2y+2xyz-10x^2z D 8xyz+10x^2z 求值3x^2y-[2xyz-(2xyz-x^2y)-4x^2y]-2xyz其中x=-2,y=-3,z=1我算到一半,怎么会有0? x>0,y=1/2(x+4/x),z=1/2(y+4/y).xyz大小关系x>0,y=1/2(x+4/x),z=1/2(y+4/y),xyz大小关系已知x、y、z满足x+y+z=xyz,求证：x(1-y^2)(1-z^2)+y(1-x^2)(1-z^2)+z(1-x^2)(1-y^2)=4xyz 3x^2y-[2x^2y-(2xyz-x^2y)-4x^2y]-2xyz,其中x=-2,y=-3,z=1 若1/2x=1/3y=1/4z,且xyz≠0,求xyz最后一段为“求x:y:z”