\(A=\left\{1;3;a;b\right\}\)
Tập con của A
\(\left\{1;3;a;b\right\},\varnothing,\left\{1\right\},\left\{3\right\},\left\{a\right\},\left\{b\right\},\left\{1;3\right\},\left\{1;a\right\},\left\{1;b\right\},\left\{3;a\right\},\left\{3;b\right\},\left\{a;b\right\},\left\{1;3;a\right\},\left\{1;3;b\right\},\left\{3;a;b\right\},\left\{b;a;1\right\}\)
B = {1;3;a;b}
C = {1;3;a}
D = {1;3;b}
E = {1;a;b}
F = {a;b;3}
G = {1;3}
H = {1;a}
I = {1;b}
J = {3;a}
K = {3;b}
L = {a} M = {b} N = {1} O = {3} P =∅