Union
From CS2800 wiki
This means that if you know , you can conclude that 'either' 'or' , and similarly you can prove if you can either prove or that .
In this Venn diagram, the union of and is shaded:
This means that if you know [math]x \href{/cs2800/wiki/index.php/%5Cin}{\in} A \href{/cs2800/wiki/index.php/%5Ccup}{\cup} B [/math], you can conclude that 'either' [math]x \href{/cs2800/wiki/index.php/%5Cin}{\in} A [/math] 'or' [math]x \href{/cs2800/wiki/index.php/%5Cin}{\in} B [/math], and similarly you can prove [math]x \href{/cs2800/wiki/index.php/%5Cin}{\in} A \href{/cs2800/wiki/index.php/%5Ccup}{\cup} B [/math] if you can either prove [math]x \href{/cs2800/wiki/index.php/%5Cin}{\in} A [/math] or that [math]x \href{/cs2800/wiki/index.php/%5Cin}{\in} B [/math].
In this Venn diagram, the union of [math]A [/math] and [math]B [/math] is shaded:
