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bonjour

ex 2

1a)

A = 1 + 2/3 = 1/1 + 2/3 = 1*3/1*3 + 2/3 = 3/3 + 2/3 = 5/3

B = 2 + 1/3 = 2/1 + 1/3 = 2*3/1*3 + 1/3 = 6/3 + 1/3 = 7/3

C = 3 + 10/7 = 3/1 + 10/7 = 3*7+/1*7 + 10/7 = 21/7 + 10/7 = 31/7

D = 1 - 3/7 = 1/1 - 3/7 = 1*7/1*7 - 3/7 = 7/7 - 3/7 = 4/7

b) A + B = 5/3 + 7/3 = 12/3 = 4

C + D = 31/7 + 4/7 = 35/7 = 5

2) A + B = 1 + 2/3 + 2 + 1/3 = 1 + 2 + (2/+1/3) = 3 + 1 = 4

C + D = 3 + 10/7 + 1 - 3/7 = 3 + 1 + (10/7 - 3/7) = 4 + 1 = 5