Bonjour
Calculer en détaillant et donner le résultat sous la forme d'une fraction irréductible
A= - 5/7 - (3/2 - 5/4)
A = (- 5 x 4) / (7 x 4) - [(3 x 14) / (2 x 14) - (5 x 7) / (4 x 7)]
A = - 20/28 - (42/28 - 35/25)
A = - 20/28 - 7/28
A = - 27/28
B= - 5/8 +5/12
B = (- 5 x 6) / (8 x 6) + (5 x 4) / (12 x 4)
B = - 30/48 + 20/48
B = - 10/48
B = (2 x - 5) / (2 x 24)
B = - 5/24
C= - 28/27 *36/7
C = - 1 008/189
C = (63 x - 16) / (63 x 3)
C = - 16/3
D=4/3 +7/6*-2/5
D = (4 x 10) / (3 x 10) - 14/30
D = 40/30 - 14/30
D = 26/30
D = (2 x 13) / (2 x 15)
D = 13/15
E= (8/15 - 2/5)*(3+9/2)
E = [8/15 - (2 x 3) / (5 x 3)] x [(3 x 2) / (1 x 2) + 9/2]
E = (8/15 - 6/15) x (6/2 + 9/2)
E = 2/15 x 15/2
E = 30/30
E = 1.
