Réponse :
Explications étape par étape
Bjr,
A)
3/2 -1/3 = 9/6 - 2/6 = 7/6
3/4 + 2/3 = 9/12 + 8/12
(7/6)/(8/12) = (7*12)/( 6*8 )= 84/48 = 42/24 = 21/12 = 7/4
B)
2/7 + 5/4 = (2*4)/ 7*5) = 8/35
2+8/35 = 70/35 +8/35 = 78/35
C)
(3)/(7/5) = (3*5)/7 = 15/7
-3/4 -15/7 +2 =
-21/28 - 60/28 +56/28 = -25/28
D)
(8/15) /(2/3) = (8*3)/ 15*2) = 24/30 = 8/15
7/5 + 8/15 -19/2 = 42/30 + 16/30 - 285/30 = -227/30
☺
