Розділ 3. КВАДРАТНІ РІВНЯННЯ » 24.14

24.14 Скоротіть дріб: 1) (x-1)/(x^2- 4x+3) = (x-1)/((x-3)(x-1)) = 1/(x-3). x² – 4x + 3 = 0. D = (–4)² – 4 • 3 = 4; x1 = (4+2)/2 = 3; x2 = (4-2)/2 = 1. 2) (x^2- 5x-14)/(x+2) = ((x-7)(x+2))/(x+2) = x – 7. x² – 5x – 14 = 0. D = (–5)² – 4 • (–14) = 81; x1 = (5+9)/2 = 7; x2 = (5-9)/2 = –2.