(a+b+c)[(a-b)^2+(b-c)^2+(c-a)^2]

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(a+b+c)[(a-b)^2+(b-c)^2+(c-a)^2]

(a+b+c)[(a-b)^2+(b-c)^2+(c-a)^2]
(a+b+c)[(a-b)^2+(b-c)^2+(c-a)^2]

(a+b+c)[(a-b)^2+(b-c)^2+(c-a)^2]
原式=(a+b+c)(2a²+2b²+2c²-2ab-2bc-2ca)
=2(a+b+c)(a²+b²+c²-ab-bc-ca)
=2(a³+b³+c³-3abc)
=2a³+2b³+2c³-6abc

=(a+b+c)(2a^2+2b^2+2c^2-2ab-2bc-2ca)
=2(a+b+c)(a^2+b^2+c^2-ab-bc-ca)
=2(a^3+b^3+c^3-3abc)
=2a^3+2b^3+2c^3-6abc

原式=(a+b+c)( a²-2ab+b² + b²-2bc+c² + c²-2ac+a²)
=(a+b+c)( 2a²+2b²+2c²-2ab-2bc-2ca)
=2a^3+2ab²+2ac²-2a²b-2abc-2ca²
+2a²b+2b^3+2bc²-2ab²-2b²c-2abc
+2a²c+2b²c+2c^3-2abc-2bc²-2ac²
=2a^3+2b^3+2c^3-6abc

=(a+b+c)(2a²+2b²+2c²-2ab-2bc-2ca)
=2(a+b+c)(a²+b²+c²-ab-bc-ca)
=2(a³+b³+c³-3abc)
=2a³+2b³+2c³-6abc

(a+b+c)[(a-b)²+(b-c)²+(c-a)²]=(a+b+c)(2a²+2b²+2c²-2ab-2bc-2ca)
=2(a+b+c)(a²+b²+c²-ab-bc-ca)
=2a^3+2ab²+2ac²-2a²b-2abc-2ca²+2a&#...

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(a+b+c)[(a-b)²+(b-c)²+(c-a)²]=(a+b+c)(2a²+2b²+2c²-2ab-2bc-2ca)
=2(a+b+c)(a²+b²+c²-ab-bc-ca)
=2a^3+2ab²+2ac²-2a²b-2abc-2ca²+2a²b+2b^3+2bc²-2ab²-2b²c-2abc+2a²c+2b²c+2c^3-2abc-2bc²-2ac²
=2(a³+b³+c³-3abc)
=2a³+2b³+2c³-6abc

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