a³ - 2ab - 2b
Проверка:
(5a³ - 2ab + 6b) - (a³ - 2ab - 2b) = 4a³ + 8b
5a³ - 2ab + 6b - a³ + 2ab + 2b = 4a³ + 8b
4a³ + 8b = 4a³ + 8b
a³ - 2ab - 2b
Проверка:
(5a³ - 2ab + 6b) - (a³ - 2ab - 2b) = 4a³ + 8b
5a³ - 2ab + 6b - a³ + 2ab + 2b = 4a³ + 8b
4a³ + 8b = 4a³ + 8b