calculer à la main: a=8-(3+11) b=8-3+11 c=12-(11-5) d=12-11-5 e=-8+(8-5) f-8+8-5

a=8-(3+11)
= 8 -(14)
= -6

 b=8-3+11
b= 5+11
b = 16

c=12-(11-5)
c = 12 -(6)
c = 12-6
c =6

d=12-11-5
d = 12-16
d = -4

ou d = 12-11-5 = 1-5 = -4

e=-8+(8-5)
= -8 +(3)
=  -5

f-8+8-5
= 0-5
= -5