■ヨハン・アルブレヒト・オイラーの不等式(その41)

 2乗すると

 36(x^2+y^2+z^2+w^2)^2

 =(x-y)^4+(z-w)^4+(x+y)^4+(z+w)^4

 +(x-z)^4+(y-w)^4+(x+z)^4+(y+w)^4

 +(x-w)^4+(y-z)^4+(x+w)^4+(y+z)^4

+2{(x-y)^2(x+y)^2+(z-w)^2(z+w)^2}

+2{(x-z)^2(x+z)^2+(y-w)^2(y+w)^2}

+2{(x-w)^2(x+w)^2+(y-z)^2(y+z)^2}

+2・・・

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[雑感]x^6+y^6+z^6+u^6+v^6+w^6-6xyzuvw

=(x^2+y^2+z^2)/2・{(y^2-z^2)^2+(z^2-x^2)^2+(x^2-y^2)^2}+(u^2+v^2+w^2)/2・{(v^2-w^2)^2+(w^2-u^2)^2+(u^2-v^2)^2}+3(xyz-uvw)^2

F=x^6+y^6+z^6+u^6+v^6+w^6

=(x^2+y^2+z^2)/2・{(y^2-z^2)^2+(z^2-x^2)^2+(x^2-y^2)^2}+(u^2+v^2+w^2)/2・{(v^2-w^2)^2+(w^2-u^2)^2+(u^2-v^2)^2}+3(xyz)^2+3(uvw)^2

についても,同様の変形が可能だろうか?

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