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