bonjour
a = 28 x + 4 - 35 x² - 5 x = - 35 x² + 23 x + 4
b = 10 x² - 20 x - 3 x + 6 = 10 x² - 23 x + 6
Bonjour,
a) (4 - 5x)(7x + 1)
= 4 × 7x + 4 × 1 - 5x × 7x - 5x × 1
= 28x + 4 - 35x² - 5x
= -35x² + 23x + 4
b) (10x - 3)(x - 2)
= 10x × x + 10x × (-2) - 3x - 3 × (-2)
= 10x² - 20x - 3x + 6
= 10x² - 23x + 6
En espérant t’avoir aidé(e) ! ^^
