1) (x - 2)² = x² - 2 * x * 2 + 2² = x² - 4x + 4
2) x⁴ + 4x² + 4 = (x²)² + 2 * 2 * x² + 2² = (x² + 2)²
3) 2(x⁴ - 16) = 2[(x²)² - 4²] = 2(x² - 4)(x² + 4) = 2(x - 2)(x + 2)(x² + 4)
1) (x - 2)² = x² - 2 * x * 2 + 2² = x² - 4x + 4
2) x⁴ + 4x² + 4 = (x²)² + 2 * 2 * x² + 2² = (x² + 2)²
3) 2(x⁴ - 16) = 2[(x²)² - 4²] = 2(x² - 4)(x² + 4) = 2(x - 2)(x + 2)(x² + 4)