Réponse:
Bonjour,
Exercice 4 :
1. a) A(-3) = 8 × (-3) - 15
= -24 - 15 = -39
b) B(2) = 3 × 2³ + 4 × 2 - 5
= 3 × 8 + 8 - 5
= 24 + 8 - 5
= 32 - 5
= 27
B(-1) = 3 × (-1)³ + 4 × (-1) - 5
= 3 × (-1) - 4 - 5
= -3 - 4 - 5
= -7 - 5
= -12
2. a) • 6
• 6 - 4 = 2
• 2² = 4
• 4 - 2 × 6 = 4 - 12 = -8
On obtient bien -8.
b) Si on prend x comme nombre de départ, on obtient : ((x - 4)²) - 2x = (x² - 16) - 2x
c) (2² - 16) - 2 × 2 = 4 - 16 - 4 = -16
