Odpowiedź:
zad 7
5mn³ + 13m²n³ - ( 5m²n³ - 2mn³) = 5mn³+ 2mn³ + 13m²n³ - 5m²n³ =
= 7mn³ + 8m²n³
4ab² - [2a²b - (2ab² - 2a²b)] = 4ab² - (2a²b - 2ab² + 2a²b) = 4ab² - (4a²b - 2ab²) =
= 4ab² - 4a²b + 2ab² = 6ab² - 4a²b
