Умножь дроби и заполни пропуски

1. \(\dfrac{a^2-ab}{a^2+ab}\cdot \dfrac{a^2b+ab^2}{ab}\) \(=\) [ ] \(=\) [ ] \(=\) [ ].
2. \(\dfrac{a^2-b^2}{a^4}\cdot \dfrac{a^4}{(a+b)^2}=\) [ ].