8 8 8 u*z + u*y - y*z - y9
u*z^8 + u*y^8 - y*z^8 - y9
8 8 -y9 + u*y + z *(u - y)
/ 8 8\ 8 -y9 + u*\y + z / - y*z
-y9 + u*(y^8 + z^8) - y*z^8
-y9 + u*y^8 + u*z^8 - y*z^8