Răspuns :
D₁₈=multimea divizorilor lui 18, D₁₈={-18, -9,-6,-3,-2,-1,1,2,3,2,9,18}
x I 12 x e natural atunci A={1,2,3,4,6,12}
a) A n D₁₈={1,2,3,6}
b) A U D₁₈={{-18, -9,-6,-3,-2,-1,1,2,3,4,6,12,18}
c) A-D₁₈={4,12}
x I 12 x e natural atunci A={1,2,3,4,6,12}
a) A n D₁₈={1,2,3,6}
b) A U D₁₈={{-18, -9,-6,-3,-2,-1,1,2,3,4,6,12,18}
c) A-D₁₈={4,12}
D₁₈={-18, -9,-6,-3,-2,-1,1,2,3,2,9,18}
x I 12 x e natural => A={1,2,3,4,6,12}
a) A n D₁₈={1,2,3,6}
b) A U D₁₈={{-18, -9,-6,-3,-2,-1,1,2,3,4,6,12,18}
c) A-D₁₈={4,12}
x I 12 x e natural => A={1,2,3,4,6,12}
a) A n D₁₈={1,2,3,6}
b) A U D₁₈={{-18, -9,-6,-3,-2,-1,1,2,3,4,6,12,18}
c) A-D₁₈={4,12}