Aidez moi svp j'ai un DM dedans je ne comprend vraiment rien Mercii. #Plusieurs réponse si possible.

Exercice 1 :

1. A = (3/5)-(1/2)*(5/2)
A = = (3/5)-(5/4)
A = = (12/20)-(25/20)
A = -13/20

B = (3-(2/3))/((4/3)*7)
B = ((9/3)-(2/3))/(28/3)
B = (7/3)/(28/3)
B = (7/3)*(3/28)
B = 21/84
B = 1/4

Donc (d'après mes calculs) A ≠ B

2. C = (8/3)-(2/3)+(8/7)
C = (6/3)+(8/7)
C = 2+(8/7)
C = (14/7)+(8/7)
C = 22/7

D = ((-2/5)+(5/2))/((-3/4)+(1/2))
D = ((-4/10)+(25/10))/((-3/4)+(2/4))
D = (21/10)/(-1/4)
D = (21/10)*(-4)
D = -84/10
D = -42/5 (simplification par 2)

3. B = 1/4
L'inverse de B est donc 4 (4/1)

D = -42/5
L'opposé de D est donc 42/5

4. B+D
= (1/4)+(-42/5)
= (5/20)-(168/20)
= -163/20

C*D 
= (22/7)*(-42/5)
= -924/35
= -132/5 (simplification par 7)

C/B
= (22/7)/(1/4)
= (22/7)*4
= 88/7