$\dfrac { 1 } { 2 } \left ( x + y - z \right ) \left ( \left ( x - y \right ) ^ { 2 } + \left ( y + z \right ) ^ { 2 } + \left ( z + x \right ) ^ { 2 } \right )$
$\color{#FF6800}{ x } ^ { \color{#FF6800}{ 3 } } \color{#FF6800}{ + } \color{#FF6800}{ y } ^ { \color{#FF6800}{ 3 } } \color{#FF6800}{ - } \color{#FF6800}{ z } ^ { \color{#FF6800}{ 3 } } \color{#FF6800}{ + } \color{#FF6800}{ 3 } \color{#FF6800}{ x } \color{#FF6800}{ y } \color{#FF6800}{ z }$
$ $ Transform into the transformation format of the multiplication formula $ $
$\color{#FF6800}{ x } ^ { \color{#FF6800}{ 3 } } \color{#FF6800}{ + } \color{#FF6800}{ y } ^ { \color{#FF6800}{ 3 } } \color{#FF6800}{ - } \color{#FF6800}{ z } ^ { \color{#FF6800}{ 3 } } \color{#FF6800}{ - } \color{#FF6800}{ 3 } \color{#FF6800}{ x } \color{#FF6800}{ y } \color{#FF6800}{ \times } \left ( \color{#FF6800}{ - } \color{#FF6800}{ z } \right )$
$\color{#FF6800}{ x } ^ { \color{#FF6800}{ 3 } } \color{#FF6800}{ + } \color{#FF6800}{ y } ^ { \color{#FF6800}{ 3 } } \color{#FF6800}{ - } \color{#FF6800}{ z } ^ { \color{#FF6800}{ 3 } } \color{#FF6800}{ - } \color{#FF6800}{ 3 } \color{#FF6800}{ x } \color{#FF6800}{ y } \color{#FF6800}{ \times } \left ( \color{#FF6800}{ - } \color{#FF6800}{ z } \right )$
$ $ Factorize to use $ x^{3}+y^{3}+z^{3}-3xyz=(x+y+z)(x^{2}+y^{2}+z^{2}-xy-yx-zx)$
$\left ( \color{#FF6800}{ x } \color{#FF6800}{ + } \color{#FF6800}{ y } \color{#FF6800}{ - } \color{#FF6800}{ z } \right ) \left ( \color{#FF6800}{ x } ^ { \color{#FF6800}{ 2 } } \color{#FF6800}{ + } \color{#FF6800}{ y } ^ { \color{#FF6800}{ 2 } } \color{#FF6800}{ + } \left ( \color{#FF6800}{ - } \color{#FF6800}{ z } \right ) ^ { \color{#FF6800}{ 2 } } \color{#FF6800}{ - } \color{#FF6800}{ x } \color{#FF6800}{ y } \color{#FF6800}{ - } \color{#FF6800}{ y } \color{#FF6800}{ \times } \left ( \color{#FF6800}{ - } \color{#FF6800}{ z } \right ) \color{#FF6800}{ - } \color{#FF6800}{ x } \color{#FF6800}{ \times } \left ( \color{#FF6800}{ - } \color{#FF6800}{ z } \right ) \right )$
$\left ( x + y - z \right ) \left ( \color{#FF6800}{ x } ^ { \color{#FF6800}{ 2 } } \color{#FF6800}{ + } \color{#FF6800}{ y } ^ { \color{#FF6800}{ 2 } } \color{#FF6800}{ + } \left ( \color{#FF6800}{ - } \color{#FF6800}{ z } \right ) ^ { \color{#FF6800}{ 2 } } \color{#FF6800}{ - } \color{#FF6800}{ x } \color{#FF6800}{ y } \color{#FF6800}{ - } \color{#FF6800}{ y } \color{#FF6800}{ \times } \left ( \color{#FF6800}{ - } \color{#FF6800}{ z } \right ) \color{#FF6800}{ - } \color{#FF6800}{ x } \color{#FF6800}{ \times } \left ( \color{#FF6800}{ - } \color{#FF6800}{ z } \right ) \right )$
$ $ Organize equations using specific formulas $ $
$\left ( x + y - z \right ) \times \color{#FF6800}{ \dfrac { 1 } { 2 } } \left ( \left ( \color{#FF6800}{ x } \color{#FF6800}{ - } \color{#FF6800}{ y } \right ) ^ { \color{#FF6800}{ 2 } } \color{#FF6800}{ + } \left ( \color{#FF6800}{ y } \color{#FF6800}{ - } \left ( \color{#FF6800}{ - } \color{#FF6800}{ z } \right ) \right ) ^ { \color{#FF6800}{ 2 } } \color{#FF6800}{ + } \left ( \color{#FF6800}{ - } \color{#FF6800}{ z } \color{#FF6800}{ - } \color{#FF6800}{ x } \right ) ^ { \color{#FF6800}{ 2 } } \right )$
$\left ( \color{#FF6800}{ x } \color{#FF6800}{ + } \color{#FF6800}{ y } \color{#FF6800}{ - } \color{#FF6800}{ z } \right ) \color{#FF6800}{ \times } \color{#FF6800}{ \dfrac { 1 } { 2 } } \left ( \left ( \color{#FF6800}{ x } \color{#FF6800}{ - } \color{#FF6800}{ y } \right ) ^ { \color{#FF6800}{ 2 } } \color{#FF6800}{ + } \left ( \color{#FF6800}{ y } \color{#FF6800}{ - } \left ( \color{#FF6800}{ - } \color{#FF6800}{ z } \right ) \right ) ^ { \color{#FF6800}{ 2 } } \color{#FF6800}{ + } \left ( \color{#FF6800}{ - } \color{#FF6800}{ z } \color{#FF6800}{ - } \color{#FF6800}{ x } \right ) ^ { \color{#FF6800}{ 2 } } \right )$
$ $ Organize the expression $ $
$\color{#FF6800}{ \dfrac { 1 } { 2 } } \left ( \color{#FF6800}{ x } \color{#FF6800}{ + } \color{#FF6800}{ y } \color{#FF6800}{ - } \color{#FF6800}{ z } \right ) \left ( \left ( \color{#FF6800}{ x } \color{#FF6800}{ - } \color{#FF6800}{ y } \right ) ^ { \color{#FF6800}{ 2 } } \color{#FF6800}{ + } \left ( \color{#FF6800}{ y } \color{#FF6800}{ - } \left ( \color{#FF6800}{ - } \color{#FF6800}{ z } \right ) \right ) ^ { \color{#FF6800}{ 2 } } \color{#FF6800}{ + } \left ( \color{#FF6800}{ - } \color{#FF6800}{ z } \color{#FF6800}{ - } \color{#FF6800}{ x } \right ) ^ { \color{#FF6800}{ 2 } } \right )$
$\dfrac { 1 } { 2 } \left ( x + y - z \right ) \left ( \left ( x - y \right ) ^ { 2 } + \left ( y \color{#FF6800}{ - } \left ( \color{#FF6800}{ - } z \right ) \right ) ^ { 2 } + \left ( - z - x \right ) ^ { 2 } \right )$
$ $ Simplify Minus $ $
$\dfrac { 1 } { 2 } \left ( x + y - z \right ) \left ( \left ( x - y \right ) ^ { 2 } + \left ( y + z \right ) ^ { 2 } + \left ( - z - x \right ) ^ { 2 } \right )$
$\dfrac { 1 } { 2 } \left ( x + y - z \right ) \left ( \left ( x - y \right ) ^ { 2 } + \left ( y + z \right ) ^ { 2 } + \left ( \color{#FF6800}{ - } \color{#FF6800}{ z } \color{#FF6800}{ - } \color{#FF6800}{ x } \right ) ^ { \color{#FF6800}{ 2 } } \right )$
$ $ If the inside of power is all negative numbers, change them to positive numbers $ $
$\dfrac { 1 } { 2 } \left ( x + y - z \right ) \left ( \left ( x - y \right ) ^ { 2 } + \left ( y + z \right ) ^ { 2 } + \left ( \color{#FF6800}{ z } \color{#FF6800}{ + } \color{#FF6800}{ x } \right ) ^ { \color{#FF6800}{ 2 } } \right )$