Réponse :
Bonjour
Explications étape par étape
A = 5/4 -3/4 (2 -1/6)
A = 5/4 -3/4 (2 X 6/6 -1/6)
A = 5/4 -3/4 (12/6 -1/6)
A = 5/4 -3/4 (11/6)
A = 5/4 -33/24
A = 5/4 X 6/6 -33/24
A = 30/24 -33/24
A = -3/24 = -1/8