ci-joint les réponses.
G= -3/5 + 7/15
G= -9/15+ 7/15
G=-2/15
H=-5/16+9/48
H= -15/48 + 9/48
H= -6/48
H= -1/8
I= -9/12+ 6/36
I= -9/12+ 2/12
I= -7/12
J= -12/14+ 4/28
J= -24/28+ 4/28
J= -20/28
J= -5/7
K= 8/50 + -15/10
K= 8/50 + -75/50
K= -67/50
L= 4/21 +8/6
L= 8/42 + 56/42
L= 64/42
L= 32/21