Tìm x

1. (x + 1)² + (x + 2)² = (2x + 1)(x - 4)
2. (x³ + 1)(x³ - 1)= (x³ + 1)² - 2x³ + 4x
3. (2x + 3)(2x - 3) = 4x (x + 7)
4. (2x - 3)² - 4x (x - 1) = 0