Réponses

2014-01-23T20:50:42+01:00
Meilleure réponse !
2014-01-23T20:52:37+01:00
Bonsoir

A = 2/3-3 / 1-2/9  = (2/3 - 9/3) : ( 9/9 - 2/9) = -7/3 : 7/9 = - 7/3 x 9/7 = - 63/21 ou - 9/3

B = 2/5 + 3/5 : ( 1-1/10) = 2/5 + 3/5 : ( 10/10 - 1/10) = 2/5 + 3/5 : 9/10 = 2/5 + 3/5 x 10/9
= 2/5 + 30/45 = 18/45 + 30/45 = 48/45

C = 5+ ( 1/8+1) : 3/4  = 5 + ( 1/8 +8/8) : 3/4 = 5 + 9/8 : 3/4 = 5 +9/8 x 4/3 = 5 + 36/24
= 5 + 9/6 = 30/6 + 9/6 = 39/6  = 13/2