Réponse :
EX1
Calculer en détaillant et donner le résultat sous forme d'une fraction irréductible
A = (2/3) - (1/3) x (5/4 + 3/2)
= (2/3) - (1/3) x (5/4 + 6/4)
= (2/3) - (1/3) x (11/4) ordre de priorité la multiplication
= (2/3) - (11/12)
= 8/12) - (11/12)
= - 3/12
= - 1/4
on obtient A = - 1/4
B = [(1/3) + 1]/[(1/3) - 1]
= [(1/3) + (3/3)]/[(1/3) - (3/3)]
= (4/3)/(-2/3)
= - 2/1
C = (- 5/2) +( 1) - (4/3) x 9
= - 5/2) + 2/2) - 12
= (- 5/2) + (2/2) - (24/2)
= (- 5 + 2 - 24)/2
= - 27/2
D = ((2/3) + 5 + (1/7)) x (1/4 + (1/3))
= ((14/21) + 105/21) + 1/7) x ( 3/12 + (4/12))
= (120/21) x (7/12)
= (12 x 10 x 7)/(3 x 7 x 12)
= 10/3
E = 5/(2 + (3/4))
= 5/((8/4) + 3/4)
= 5/11/4
= 20/11
Explications étape par étape
