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