2 u 2 v 4 − 7 u 2 v 3 + 8 u 2 v 2 − 3 u 2 v − 2 u v 4 + 9 u v 3 − 15 u v 2 + 9 u v − 2 u − 3 v 3 + 8 v 2 − 7 v + 2 u v 2 {\displaystyle {\frac {2u^{2}v^{4}-7u^{2}v^{3}+8u^{2}v^{2}-3u^{2}v-2uv^{4}+9uv^{3}-15uv^{2}+9uv-2u-3v^{3}+8v^{2}-7v+2}{uv^{2}}}}