− v 2 u 4 + 3 v u 4 − 2 u 4 + 3 v 2 u 3 − 8 v u 3 + 4 u 3 − 4 v 2 u 2 + 9 v u 2 − 4 u 2 + 4 v 2 u − 8 v u + 3 u − 2 v 2 + 3 v − 1 {\displaystyle -v^{2}u^{4}+3vu^{4}-2u^{4}+3v^{2}u^{3}-8vu^{3}+4u^{3}-4v^{2}u^{2}+9vu^{2}-4u^{2}+4v^{2}u-8vu+3u-2v^{2}+3v-1}
