Bonjour
1)
A = - 5 + 4 - (- 5) - 3 - 1
A = - 5 + 4 + 5 - 3 - 1
A = - 5 + 5 + 4 - 1 - 3
A = 0.
B = 7 x 8 + 9 x (- 9 + 3)
B = 56 + 9 x (- 6)
B = 56 - 54
B = 2.
2)
C = 1/9 - 15/9 x 1/6 + 2/3
C = 1/9 - 15/54 + 2/3
C = (1 x 6) / (9 x 6) - 15/54 + (2 x 18) / (3 x 18)
C = 6/54 - 15/54 + 36/54
C = 42/54 - 15/54
C = 27/54
C = (27 x 1) / (27 x 2)
C = 1/2
D = 15 : (1/4 - 2/3)
D = 15 : [(1 x 3) / (4 x 3) - (2 x 4) / (3 x 4)]
D = 15 : (3/12 - 8/12)
D = 15 : (- 5/12)
D = 15 x (- 12/5)
D = - 180/5
D = (5 x - 36) / (5 x 1)
D = - 36.
