− v 2 u 4 + v u 4 + 4 v 2 u 3 − 7 v u 3 + 2 u 3 − 5 v 2 u 2 + 11 v u 2 − 5 u 2 + 2 v 2 u − 7 v u + 4 u + v − 1 {\displaystyle -v^{2}u^{4}+vu^{4}+4v^{2}u^{3}-7vu^{3}+2u^{3}-5v^{2}u^{2}+11vu^{2}-5u^{2}+2v^{2}u-7vu+4u+v-1}
