− u v 3 − 6 u v 2 + 8 u v − 2 u − 2 v 3 + 8 v 2 − 6 v + 1 u v 3 / 2 {\displaystyle -{\frac {uv^{3}-6uv^{2}+8uv-2u-2v^{3}+8v^{2}-6v+1}{{\sqrt {u}}v^{3/2}}}}
