Упростите выражения. 1) 3y (y-2x) + 6y (x-y)

2) (3a+4) (9a² - 12a + 16)

3) (3t + 2) (3t - 3) - (3t - 1) ²

4) (2b - b) ³ + b³ + 12b

3y (y - 2x) + 6y (x - y) = 3y² - 6xy + 6xy - 6y² = - 3y²

(3a + 4) (9a² - 12a + 16) = 27a³ - 36a² + 48a + 36a² - 48a + 64 = 27a³ + 64

(3t + 2) (3t - 3) - (3t - 1) ² = 9t² - 9t + 6t - 6 - 9t² + 6t - 1 = 3t - 7

(2b - b) ³ + b³ + 12b = b³ + b³ + 12b = 2b³ + 12b