Ex 9 Calcul relatif Ex 31 a

ex 9 :

(4/6 - 5/3) : (3/4 + 3/16)
= (4 /6 - 10/6) : (12/16 + 3/16)
= - 1 x 16/15
= - 16/15

(5/16 - 7/2) / (7/8 + 1)
= (5/16 - 56/16) / (7/8 + 8/8)
= - 51/16 x 8/15
= - 408/240
= - 17/10

ex 31 :

(7/2 - 1) / (6/5 + 3)
= (7/2 - 2/2) / (6/5 + 15/5)
= 5/2 x 5/21
= 25/42