u v 3 w 3 − u v 3 w 2 − u v 2 w 3 + 2 u v 2 w 2 − 2 v w + v + w − 1 u v 3 / 2 w 3 / 2 {\displaystyle {\frac {uv^{3}w^{3}-uv^{3}w^{2}-uv^{2}w^{3}+2uv^{2}w^{2}-2vw+v+w-1}{{\sqrt {u}}v^{3/2}w^{3/2}}}}
