bjr
3/4 - 5/8 = 6/8 - 5/8 = 1/8 ok
= (6x28)/14 x 10/10⁻³ = 12 x 10⁻² = 0,12 - donc B pas C
= x² - 2x - x + 2 - x² = -3x + 2 ok
= 2 * (-2)² - 5 * (-2) + 3 = 8 + 10 + 3 = 21 ok
= (x-5) [(x-5)+(2x+1) = (x-5) (3x - 4) B pas A
5 km en 1,25h donc en 1h => v = 5 : 1,25 = 4 km/h ok