Répondre :
A = 1/2 + 3/4 - 5/6
A = 6/12 + 9/12 - 10/12
A = 15/12 - 10/12
A = 5/12
B = 40/9 - (4/3 - 2/9)
B = 40/9 - (12/9 - 2/9)
B = 40/9 - 10/9
B = 30/9
B = 10/3
A = 6/12 + 9/12 - 10/12
A = 15/12 - 10/12
A = 5/12
B = 40/9 - (4/3 - 2/9)
B = 40/9 - (12/9 - 2/9)
B = 40/9 - 10/9
B = 30/9
B = 10/3