7 Calculer les produits suivants.
a.(-1) × (-2) × (-2) x (+1) x (-3)
b.(-4) × (-1) × (-1) x (+2) × (-3) × (-1)
c. (+5) × (-2) x (+2) × (+5) × (-1)
d. (-8) x (+2) x (+1) x (+1) x (-2) × (-2) × (-2)
8 Calculer les quotients suivants