Pouvez vous m’aider pour l’exercice 2 svp ?

Bonjour

Effectuer les opérations :

3/7 + 4/21

= (3 x 3)/(7 x 3) + 4/21

= 9/21 + 4/21

= (9 + 4)/21

= 13/21

-1/3 + 1

= -1/3 + (1 x 3)/(1 x 3)

= -1/3 + 3/3

= (-1 + 3)/3

= 2/3

1/2 + 1/4 + 1/8

= (1 x 4)/(2 x 4) + (1 x 2)/(4 x 2) + 1/8

= 4/8 + 2/8 + 1/8

= (4 + 2 + 1)/8

= 7/8

5/12 - 2/3

= 5/12 - (2 x 4)/(3 x 4)

= 5/12 - 8/12

= (-3/12)

= -3/(3 x 4)

= -1/4

1/2 x 8/6 x 3/2

= (1 x 8 x 3)/(2 x 6 x 2)

= (2 x 2 x 2 x 3)/(2 x 2 x 3 x 2)

= 1

-5/2 x (-2/3) x 3/5

= [-5 x (-2) x 3] / (2 x 3 x 5)

= 30/30

= 1

[(-2) x 5 x (-4) x 3 x 7 x (-5)] / [(-10) x 6]

= (-10 x (-2) x 2 x 3 x 7 x (-5)) / (-10 x 2 x 3)

= (-2) x 7 x (-5) x (-10 x 2 x 3)/(-10 x 2 x 3)

= 10 x 7

= 70