Bài 44:
a. $A=\left\{0;1;2;3\right\}$
$B=\left\{3;4\right\}$
b. $C=\left\{0;1;2\right\}$
$D=\left\{4\right\}$
$E=\left\{5;6;7;8\right\}$
c. Các tập hợp có thể là:
$\left\{0;3\right\}$; $\left\{0;4\right\}$; $\left\{1;3\right\}$; $\left\{1;4\right\}$; $\left\{2;3\right\}$; $\left\{2;4\right\}$; $\left\{3;4\right\}$
