− u 4 v 2 − u 4 v + 2 u 3 v 3 − 6 u 3 v 2 + 4 u 3 v − u 3 + u 2 v 4 − 6 u 2 v 3 + 9 u 2 v 2 − 6 u 2 v + u 2 − u v 4 + 4 u v 3 − 6 u v 2 + 2 u v − v 3 + v 2 u 2 v 2 {\displaystyle -{\frac {u^{4}v^{2}-u^{4}v+2u^{3}v^{3}-6u^{3}v^{2}+4u^{3}v-u^{3}+u^{2}v^{4}-6u^{2}v^{3}+9u^{2}v^{2}-6u^{2}v+u^{2}-uv^{4}+4uv^{3}-6uv^{2}+2uv-v^{3}+v^{2}}{u^{2}v^{2}}}}
