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