Bonsoir j'ai besoin d'aide pour l'exercice 30 et 31 je ne comprend svp
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Bonsoir,
Exercice 30
A= (2/3)/4 = 2/ 3*4 = 2/12 =1/6
B= 2/(2/3) = (2*3) /2 = 6/2 = 3
C=
1/2 -1/4 = 2/4 -1/4 = 1/4
(1/4)/(1/4 ) = 1
D= 2/3 -1 = 2/3 - 3/3 = -1/3
2/3+1 = 2/3 +3/3 = 5/3
(-1/3) / (5/3) = (-1*3)/ (3*5) = -3/15
Exercice 31
A=9/12 -8/12 +18/12 = 19/12
B= 3/4 -6/6 = 3/4 -1 = 3/4 -4/4 = -1/4
C= 3/(1/2) = 6
6*3/2 = 18/2 = 9
D= 1-1/2 = 2/2 -1/2 = 1/2
5*1/6 = 5/6