Réponse :
Explications étape par étape
Bonsoir
Soient deux expressions A et B : A = x (4 x – 1) – x ; B = (2 x² - x) × 2
1°) Calculer ces deux expressions pour : a) x = 3 b) x = -1
A = 3(4 * 3 - 1) - 3
A = 3(12 - 1) - 3
A = 3 * 11 - 3
A = 33 - 3
A = 30
A = 3(4 * (-1) - 1) - (-1)
A = 3(-4 - 1) + 1
A = 3 * (-5) + 1
A = -15 + 1
A = -14
B = (2 * 3² - 3) × 2
B = (2 * 9 - 3) * 2
B = (18 - 3) * 2
B = 15 * 2
B = 30
B = (2 (-1)² - (-1)) × 2
B = (2 * 1 + 1) * 2
B = (2 + 1) * 2
B = 3 * 2
B = 6
