1. Сократите дробь: a) 14a⁴b/49a³b²; b) 3x/(x² + 4x); c) (y² - z²)/(2y + 2z).

Решение: a) 14a⁴b/49a³b² = (14/49) * (a⁴/a³) * (b/b²) = 2/7 * a * (1/b) = 2a/(7b). b) 3x/(x² + 4x) = 3x/(x(x + 4)) = 3/(x + 4). c) (y² - z²)/(2y + 2z) = ((y - z)(y + z))/(2(y + z)) = (y - z)/2.