3. Two marks example problems I

1. If $U =\{c, d, e, f, g, h, i, j\}$ and $A = \{c, d, g, j\}$, find $A'$.

 

$A'$ $=$ $\left\{i,i,i,i\right\}$

[Note: Enter the letters in the alphabetical order.]

 

2. If $A =\{1, 2, 6\}$ and $B = \{2, 3, 4\}$, find $A \cup B$.

 

$A \cup B$ $=$ $\left\{i,i,i,i,i\right\}$

[Note: Enter the letters in ascending order.]

 

3. Let $A = \{x : x$ is an even natural number and $\ 1 < x \le 12\}$ and $B = \{x : x$, is a multiple of $3$, $x \in \mathbb{N}$ and $x \le 12\}$ be two sets. Find $A \cap B$.

 

$A \cap B$ $=$ $\left\{i,i\right\}$

[Note: Enter the letters in ascending order.]

 

4. If $A =\{2, 3\}$ and $C = \{\}$, find $A \cap C$.

 

$A \cap C$ $=$ $\{3\}$$\{2, 3\}$$\{\}$$\{2\}$