Hej!
(x - 1)(x + 3) = x² + 3x - x - 3 =
= x² + 2x - 3
(x + 2)(x - 4) = x² - 4x + 2x - 8 =
= x² - 2x - 8
(x + 1)(2x - 3) = 2x² - 3x + 2x - 3 =
= 2x² - x - 3
(4x + 2)(5x - 1) = 20x² - 4x + 10x - 2 =
= 20x² + 6x - 2
(x² - 1)(x + 3) = x³ + 3x² - x - 3
Pozdrawiam! - Julka
