If $A = \{1, 2, 3, 4\}$ and $B = \{3, 4, 5, 6\}$, then find the following: (i) $A \cap B$ (ii) $A - B$

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> [!TLDR]
> $A \cap B = \{3,4\}$ and $A-B=\{1,2\}$.
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> Given $A = \{1, 2, 3, 4\}$ and $B = \{3, 4, 5, 6\}$.
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> **(i) $A \cap B$** — the elements common to both sets: comparing element by element, $3$ and $4$ appear in both $A$ and $B$. So $A \cap B = \{3, 4\}$.
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Operation	What it asks	Bucket contains
Union ( $A \cup B$ )	In either?	Everything from $A$ or $B$ (or both)
Intersection ( $A \cap B$ )	In both?	Only the overlap
Difference ( $A \setminus B$ )	In $A$ but not $B$ ?	Just the part of $A$ that doesn't touch $B$
Complement ( $A^c$ )	Not in $A$ ?	Everything outside $A$ (inside $U$ )
Symmetric Difference ( $A \triangle B$ )	In exactly one?	The two crescent-shaped parts, excluding the overlap

Q.If $A = \{1, 2, 3, 4\}$ and $B = \{3, 4, 5, 6\}$ , then find the following:

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Q.If A={1,2,3,4}A = \{1, 2, 3, 4\}A={1,2,3,4} and B={3,4,5,6}B = \{3, 4, 5, 6\}B={3,4,5,6}, then find the following:

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Q.If $A = \{1, 2, 3, 4\}$ and $B = \{3, 4, 5, 6\}$ , then find the following:

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