Răspuns:
1. a)-1+2-1=0
b)-3+2+1=0
c)-3-2+4=-1 => fals
d)-5+2+1=-2=> fals
2. a)4-3-1=0
b)-2+12=0
c)6+6-9=3=> fals
d)-5radical6+7radical6=2radical6
sper ca te-am ajutat
