Bonsoir,
Exercice 2 :
A = 4/3 x (3/10 + 3/5)
A = 4/3 x 3/10 + 4/3 x 3/5
B = 2/5 x 13/7 + 2/5 x 1/7
B = 2/5 x (13/7 + 1/7)
C = 12 x (7/3 - 5/4)
C = 12 x 7/3 - 12 x 5/4
D = 6/5 x 1/2 + 6/5 x 2/3
D = 6/5 x (1/2 + 2/3)
Exercice 3 :
A = 3a + 2b
A = 3 x 3/4 + 2 x 5/2
A = 9/4 + 5
A = 29/4 = 7,25
B = 4ab
B = 4 x 3/4 x 5/2
B = 3 x 5/2
B = 15/2 = 7,5
C = (a+b)(b-a)
C = (3/4 + 5/2)(5/2 - 3/4)
C = 13/4 x 7/4
C = 91/16
D = 5/3a - 1/6b
D = 5/3 x 3/4 - 1/6 x 5/2
D = 5/4 - 5/12
D = 5/6
:)
