s'il vous plaît qui peut maider ?​

Bonjour,

A = 3 - (3/56 - 3/24)

A = 3 - (3/(8 * 7) - 3/(8 * 3))

A = 3 - ((3 * 3)/(8 * 7 * 3) - (3 * 7)/(8 * 3 * 7))

A = 3 - (9/168 - 21/168)

A = 3 - (-12/168)

A = 3/1 + 12/168

A = 3/1 + 12/(12 * 14)

A = (3 * 14)/(1 * 14) + 1/14

A = 42/14 + 1/14

A = 43/14

B = 1 / (4/14 + 2/8)

B = 1 / (4/(7 * 2) + 2/(4 * 2))

B = 1 / (4/(7 * 2) + 1/4)

B = 1 / ((4 * 4)/(7 * 2 * 4) + (1 * 7 * 2)/(4 * 7 * 2))

B = 1 / (16/56 + 14/56)

B = 1 / (30/56)

B = 1 * 56/30 diviser par un nombre c'est multiplier par son inverse

B = 56/30

B = (7 * 8)/(6 * 5)

B = (7 * 4 * 2)/(3 * 2 * 5)

B = (7 * 4)/(3 * 5)

B = 28/15

C = (3/2 - 5/3) / (-3/7 + 1)

C = ((3 * 3)/(2 * 3) - (5 * 2)/(3 * 2)) / (-3/7 + 1/1)

C = (9/6 - 10/6) / (-3/7 + 7/7)

C = (-1/6) / (4/7)

C = -1/6 * 7/4

C = (-1 * 7)/(6 * 4)

C = -7/24