а) (7m + 8) x (7 + 8) = 49m + 64 = 64 + 49m
б) (9m^2 - 10 n^2) x (-9m^2 - 10n^2) = -81m^4 + 100n^4 = 100n^4 - 81m^4
а) (7m + 8) x (7 + 8) = 49m + 64 = 64 + 49m
б) (9m^2 - 10 n^2) x (-9m^2 - 10n^2) = -81m^4 + 100n^4 = 100n^4 - 81m^4