![](\"resources/question-resources/384px-Venn0111.svg.png\")
The union of two sets is the set of elements from either set
\n$ A \\cup B = \\left\\{ x\\, |\\, x \\in A \\text{ or } x \\in B\\right\\}$
\nWe can think of this as the elements: in $A$ OR in $B$ OR in Both
\nThe intersection of two sets is the set of elements common to both sets
\n$ A \\cap B = \\left\\{ x\\, |\\, x \\in A \\text{ and } x \\in B\\right\\}$
\nWe can think of this as the elements: in $A$ AND in $B$
\nThe difference $A-B$ is the set of elements from $A$ which are not in $B$:
\n$ A - B = \\left\\{ x \\in A |\\, x \\notin B\\right\\}$
\nWe can think of this as the elements: in $A$ but NOT in $B$
\nSimilarly, the difference $B-A$ is the set of elements from $B$ which are not in $A$:
\n$ B - A = \\left\\{ x \\in B |\\, x \\notin A\\right\\}$
\nWe can think of this as the elements: in $B$ but NOT in $A$
\nThe symmetric difference $A \\Delta B$ is the union of the set differences, but it can also be expressed as the union minus the intersection
\n$ A \\Delta B = (A \\cup B) - (A \\cap B)$.
\nWe can think of this as the elements: in $A$ OR in $B$ but NOT in Both.
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![](\"resources/question-resources/384px-Venn0001.svg.png\")
![](\"resources/question-resources/384px-Venn0110.svg.png\")
![](\"resources/question-resources/240px-Venn0100.svg.png\")
Match the mathematical expression with its Venn diagram.
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