− ( v − 1 ) ( w − 1 ) ( 2 u w 3 − 2 u w 2 + 2 u w − u + w 4 − 2 w 3 + 2 w 2 − 2 w ) u v w 5 / 2 {\displaystyle -{\frac {(v-1)(w-1)\left(2uw^{3}-2uw^{2}+2uw-u+w^{4}-2w^{3}+2w^{2}-2w\right)}{{\sqrt {u}}{\sqrt {v}}w^{5/2}}}}
