Bonjour
E = (1 - 1/3)/3 x 3/4 - 1/5
E = (3/3 - 1/3)/3 x 3/4 - 1/5
E = (2/3)/3 x 3/4 - 1/5
E = 2/(3 x 3) x 3/4 - 1/5
E = 2/3 x 1/4 - 1/5
E = 2/12 - 1/5
E = 2/(2 x 6) - 1/5
E = 1/6 - 1/5
E = 5/30 - 6/30
E = (-1/30)
F = -5/14 + 3 x 1/42
F = -5/14 + 3/(3 x 14)
F = -5/14 + 1/14
F = -4/14
F = (-2 x 2)/(2 x 7)
F = (-2/7)
D = (1 - 1/3)/(1/4 - 2)
D = (3/3 - 1/3)/(1/4 - 8/4)
D = (2/3)/(-7/4)
D = -2/3 x 4/7
D = -8/21
