Б) (3m - n - k)²+ 2(3mn + 3mk - nk) = 9m²+ (-n)²+ (-k)²- 6mn - 6 km + 2kn + 2(3mn + 3km - kn) = 9m² + (-n)² + (-k)² - 6mn - 6km + 2kn + 6mn + 6km - 2kn = 9m² + n² + k²
в) (4a + 2b - 3)² - (4a - 2b + 3)² = (4a + 2b - 3 - (4a - 2b + 3)) * (4a + 2b - 3 + (4a - 2b + 3)) = (4a + 2b - 3 - 4a + 2b - 3) * (4a + 2b - 3 + 4a - 2b + 3) = (4b - 6) * 8a = 2(2b - 3) * 8a = 2 * 8a * (2b - 3) = 16a * (2b - 3) = 32ab - 48a