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