Réponses

2014-03-02T15:15:16+01:00
B = (-2x + 1)² - 3(2x + 1)(x - 2)
B = (-2x)² + 2 x (-2x) x 1 + 1² - 3 (2x² - 4x + x - 2)
B = 4x² - 4x + 1 -3(2x² - 3x - 2)
B = 4x² - 4x + 1 - 6x² + 9x + 6
B = -2x² + 5x + 7