u 2 v 4 − 4 u 2 v 3 + 5 u 2 v 2 − 2 u 2 v − u v 4 + 7 u v 3 − 11 u v 2 + 7 u v − u − 2 v 3 + 5 v 2 − 4 v + 1 u v 2 {\displaystyle {\frac {u^{2}v^{4}-4u^{2}v^{3}+5u^{2}v^{2}-2u^{2}v-uv^{4}+7uv^{3}-11uv^{2}+7uv-u-2v^{3}+5v^{2}-4v+1}{uv^{2}}}}