− 6 u v 2 − 9 u v + 4 u + 4 v 3 − 9 v 2 + 6 v u v 3 / 2 {\displaystyle -{\frac {6uv^{2}-9uv+4u+4v^{3}-9v^{2}+6v}{{\sqrt {u}}v^{3/2}}}}
