x+y+z=0求 x3+y3+z3=?
来源:学生作业帮 编辑:拍题作业网作业帮 分类:数学作业 时间:2024/04/26 06:31:08
x+y+z=0求 x3+y3+z3=?
(x+y+z)^3=0
如果你不知道三项的展开式的话 先把x+y看成一项
(x+y+z)^3
=(x+y)^3+z^3+3(x+y)^2z+3(x+y)z^2
=x^3+y^3+z^3+3x^2y+3xy^2+3(x+y)^2z+3(x+y)z^2
=x^3+y^3+z^3+3xy(x+y)+3(x+y)^2z+3(x+y)z^2
=x^3+y^3+z^3+3(x+y)[xy+(x+y)*z+z^2]
=x^3+y^3+z^3+3(x+y)(xy+xz+yz+z^2)
=x^3+y^3+z^3+3(x+y)(x+z)(y+z)
=0
x^3+y^3+z^3=-3(x+y)(x+z)(y+z)
x+y+z=0
x+y=-z
y+z=-x
x+z=-y
x^3+y^3+z^3=3xyz
按你的意思我只能算出这个结果 不给xyz的乘积 没办法算出具体值
如果你不知道三项的展开式的话 先把x+y看成一项
(x+y+z)^3
=(x+y)^3+z^3+3(x+y)^2z+3(x+y)z^2
=x^3+y^3+z^3+3x^2y+3xy^2+3(x+y)^2z+3(x+y)z^2
=x^3+y^3+z^3+3xy(x+y)+3(x+y)^2z+3(x+y)z^2
=x^3+y^3+z^3+3(x+y)[xy+(x+y)*z+z^2]
=x^3+y^3+z^3+3(x+y)(xy+xz+yz+z^2)
=x^3+y^3+z^3+3(x+y)(x+z)(y+z)
=0
x^3+y^3+z^3=-3(x+y)(x+z)(y+z)
x+y+z=0
x+y=-z
y+z=-x
x+z=-y
x^3+y^3+z^3=3xyz
按你的意思我只能算出这个结果 不给xyz的乘积 没办法算出具体值
已知X+Y+Z=0,求X3次方+Y3次方+Z3次方等于多少?
已知x+y+z=1,x2+y2+z2=2,x3+y3+z3=3,求xy(x+y)+yz(y+z)+zx(z+x)的值
已知x+y+z=2,x2+y2+z2=12则x3+y3+z3=
x2+y2+z2=2007 ,x3+y3+z3=2008.求√x/y+√y/z+√z/x=?
因式分解(x+y+z)3-x3-y3-z3
已知x,y,z都是正整数,并且x3-y3-z3=3xyz,x2=2(y-z),求xy+yz+zx
已知x+y+z=3,x2+y2+z2=19,x3+y3+z3=30则xyz=?
若x,y,z大于等于0,求证:x3+y3+z3大于等于3xyz
已知x+y+z=1 x2+y2+z2=2 x3+y3+z3=3 求x4+y4+z4=?
因式分解X2(Y+Z)+Y2(Z+X)+Z2(X+Y)-(X3+Y3+Z3)-2XYZ
x3(y-z)+y3(z-x)+z3(x-y)
x3+y3+z3+(x+y)3+(y+z)3+(z+x)3因式分解