Réponses

2014-01-30T20:37:57+01:00
2/3 - 5/3 x (1 - 7/5) = 2/3 - 5/3 x (1 x 5 / 1 x 5 - 7/5) = 2/3 - 5/3 x (5/5 - 7/5) = 2/3 - 5/3  x -2/5 = 2/3 - 10/15 = 2 x 5 / 3 x 5 - 10/15 = 10/15 - 10/15 = 0

5/6 - 5/4 
= 5 x 2 / 6 x 2 - 5 x 3 / 4 x 3 = 10/12 - 15/12 = -5/12 : 5/8 = -5/12 x 8/5 = -40/60
   5/8                          5/8                              5/8
= 20 x 3 / 20 x 2 = 3/2