Bonjour
a. a = - 1 ; b = 1/3 ; c = 2/5
A = a/b + c
A = - 1 : 1/3 + 2/5
A = - 1 x 3 + 2/5
A = - 3 + 2/5
A = (- 3 x 5) / (1 x 5) + 2/5
A = - 15/5 + 2/5
A = - 13/5
B = (a + b) / c
B = (- 1 + 1/3) / 2/5
B = [(- 1 x 3) / (1 x 3) + 1/3] : 2/5
B = (- 3/3 + 1/3) : 2/5
B = - 2/3 : 2/5
B = - 2/3 x 5/2
B = - 10/6
B = (2 x - 5) / (2 x 3)
B = - 5/3
C = a / (b + c)
C = - 1 : (1/3 + 2/5)
C = - 1 : [(1 x 5) / (3 x 5) + (2 x 3) /(5 x 3)]
C = - 1 : (5/15 + 6/15)
C = - 1 : 11/15
C = - 1 x 15/11
C = - 15/11
b.
B = (a + b) / c
B = (1/2 - 5/4) : 3/4
B = [(1 x 2) / (2 x 2) - 5/4] : 3/4
B = (2/4 - 5/4) : 3/4
B = - 3/4 : 3/4
B = - 3/4 x 4/3
B = - 12/12
B = - 1
C = a / (b + c)
C = 1/2 : (- 5/4 + 3/4)
C = 1/2 : - 2/4
C = 1/2 x - 4/2
C = - 4/4
C = - 1.
Julia a raison.
