− v 2 u 4 + 3 v u 4 − 2 u 4 + 4 v 2 u 3 − 11 v u 3 + 6 u 3 − 7 v 2 u 2 + 17 v u 2 − 7 u 2 + 6 v 2 u − 11 v u + 4 u − 2 v 2 + 3 v − 1 {\displaystyle -v^{2}u^{4}+3vu^{4}-2u^{4}+4v^{2}u^{3}-11vu^{3}+6u^{3}-7v^{2}u^{2}+17vu^{2}-7u^{2}+6v^{2}u-11vu+4u-2v^{2}+3v-1}