Réponses

2014-05-27T19:18:37+02:00
-7/7 : (5/14 + 5/6)
= - 7/7 : (5 x 3 / 14 x 3 + 5 x 7 / 6 x 7)
= - 7/7 : (15/42 + 35/42)
= - 7/7 : 50/42
= - 7/7 x 42/50
= - 294/350
= 14 x - 21 / 14 x 25
= - 21/25