− u v 5 − 4 u v 4 + 7 u v 3 − 8 u v 2 + 7 u v − 2 u − 2 v 5 + 7 v 4 − 8 v 3 + 7 v 2 − 4 v + 1 u v 5 / 2 {\displaystyle -{\frac {uv^{5}-4uv^{4}+7uv^{3}-8uv^{2}+7uv-2u-2v^{5}+7v^{4}-8v^{3}+7v^{2}-4v+1}{{\sqrt {u}}v^{5/2}}}}