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