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