Réponses

  • Utilisateur Brainly
2014-09-08T19:02:22+02:00
A= 2/5 - 14/15
= (2*3)/(5*3) - 14/15
= 6/15 - 14/15
= - 8/15

B= 1/3 - 1/2 
= (1*2)/(3*2) - (1*3)/(2*3)
= 2/6 - 3/6
= - 1/6

C=4/3 - 4/5 
= (4*5)/(3*5) - (4*3)/(5*3)
= 20/15 - 12/15
= 8/15

D= 8/7 - 6/3
= (8*3)/(7*3) - (6*7)/(3*7)
= 24/21 - 42/21
= - 18/21
2014-09-08T19:11:34+02:00
A = 2 / 5 - 14 / 15
= 6 / 15 - 14 / 15
= - 8 / 15

B= 1 / 3 - 1 / 2 
= 2 / 6 - 3 / 6
= - 1 / 6

C=4 / 3 - 4 / 5 
= 20 / 15 - 12 / 15
= 8 / 15

D= 8 / 7 - 6 / 3
= 24 / 21 - 42 / 21
= - 18 / 21
= - 6 / 7