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