Réponse :
EXERCICE 1
1) A= 5 + (10 - 2X5)= 5+(10 - 10)=5+0=5
2) B= 15 / (2+ (6-3))= 15/(2+3)=15/5=3
EXERCICE 2
1) A=5x² - 1 = 5(2²) - 1= 5X4 - 1=20 - 1 = 19
B=(2x + 3)(5x - 4) = (2X2 +3)(5X2 -4)= (4+3)(10-4)=12X6=72
2) C=5(3+6x) =5(3 + (6X2)) =5(3 + 12) =5 X 15 =75
D= (5 - x) + x(x + 3) = (5 - 2) + 2 (2 + 3) =3 + 2X5 = 3 + 10 = 13
Explications étape par étape