Bonjour
Effectuer les calculs suivants et donner le résultat sous la forme d'une fraction irréductible.
M=(8/21 +9/14)(1/8--5/24)
M = [(8 x 2) / (21 x 2) + (9 x 3) / (14 x 3)] [(1 x 3) / (8 x 3) - 5/24]
M = (16/42 + 24/42) (3/24 - 5/24)
M = 40/42 x - 2/24
M = - 80/1 008
M = (16 x - 5) / (16 x 63)
M = - 5/63
N= 1/3-1/3×6/7
N = 1/3 - 6/21
N = (1 x 7) / (3 x 7) - 6/21
N = 7/21 - 6/21
N = 1/21
O=1/2-6/7×42/30+11/9
O = 1/2 - 252/210 + 11/9
O = 1/2 - (42 x 6) / (42x 5) + 11/9
O = 1/2 - 6/5 + 11/9
O = (1 x 45) / (2 x 45) - (6 x 18) / (5 x 18) + (11 x 10) / (9 x 10)
O = 45/90 - 108/90 + 110/90
O = 47/90.
