− ( u − 1 ) ( v − 1 ) ( 2 u 2 v 2 − u 2 v − 2 u v 2 + 4 u v − 2 u − v + 2 ) u 3 / 2 v 3 / 2 {\displaystyle -{\frac {(u-1)(v-1)\left(2u^{2}v^{2}-u^{2}v-2uv^{2}+4uv-2u-v+2\right)}{u^{3/2}v^{3/2}}}}
