Réponses

2013-11-12T17:44:19+01:00
A = 5/2-8/5x15/28
   = 5/2-120/140
   = 350/140-120/140=230/140 ou 23/14
B = (8/7-2)x(5/6-1)
   = (8/7-14/7)x(5/6-6/6)
   =-6/7x-1/6=6/42 ou 1/7