Réponses

2014-01-17T09:52:43+01:00
((a - ab) / (-b + a)) / (2)
= (1/2) * ((a - ab) / (-b +a))
= (a - ab) / 2(-b + a)

((b - ab) / (b - a)) / (2)
= (1/2) * ((b - ab) / (b-a))
= (b - ab) / 2(b - a)