Задание 3
А) 4х² - (х-3у)² = 4х² - (х²-6ху+9у²) = 4х² - х²+6ху-9у² = (4х²-9у²) (6ху-х²) = (2х-3у)(2х+3у)(6у-х)*х
Б)(2а+7b)²-(3a-5b)² = ((2a-7b)-(3a-5b))((2a-7b)+(3a-5b)) = (2a-7b-3a+5b)(2a-7b+3a-5b) = (-a-2b)(5a-12b) = - (a+2b)(5a-12b)
Задание 4
А) (y+4)(y²-4y+16) = y³ + 64
Б) (k+3)(k-11)+(k+6)² = (k²-11k+3k-33)+(k²+12k+36) = k²-8k-33+k²+12k+36 = 2k²+4k+3