问道数学题,我们没学三次方的化简,所以请用二次方的完全平方等公式解答,x+y+z=0求 x3+y3+z3=?那个3是三次方
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![问道数学题,我们没学三次方的化简,所以请用二次方的完全平方等公式解答,x+y+z=0求 x3+y3+z3=?那个3是三次方](/uploads/image/z/3890544-24-4.jpg?t=%E9%97%AE%E9%81%93%E6%95%B0%E5%AD%A6%E9%A2%98%2C%E6%88%91%E4%BB%AC%E6%B2%A1%E5%AD%A6%E4%B8%89%E6%AC%A1%E6%96%B9%E7%9A%84%E5%8C%96%E7%AE%80%2C%E6%89%80%E4%BB%A5%E8%AF%B7%E7%94%A8%E4%BA%8C%E6%AC%A1%E6%96%B9%E7%9A%84%E5%AE%8C%E5%85%A8%E5%B9%B3%E6%96%B9%E7%AD%89%E5%85%AC%E5%BC%8F%E8%A7%A3%E7%AD%94%2Cx%2By%2Bz%3D0%E6%B1%82+x3%2By3%2Bz3%3D%3F%E9%82%A3%E4%B8%AA3%E6%98%AF%E4%B8%89%E6%AC%A1%E6%96%B9)
问道数学题,我们没学三次方的化简,所以请用二次方的完全平方等公式解答,x+y+z=0求 x3+y3+z3=?那个3是三次方
问道数学题,我们没学三次方的化简,所以请用二次方的完全平方等公式解答,
x+y+z=0求 x3+y3+z3=?
那个3是三次方
问道数学题,我们没学三次方的化简,所以请用二次方的完全平方等公式解答,x+y+z=0求 x3+y3+z3=?那个3是三次方
(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 没办法算出具体值求采纳
(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+...
全部展开
(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
你可以去学习工具上找一下答案,我每次都是这样的,不会的题目直接拍照上传到魔方格作业神器,就会有学霸帮你解答的
收起
0,肯定是0