Does the Union Notation in Abstract Algebra Allow for Multiple Matches for x?

freefizix
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This question links to a former discussion on the board. I'm confused regarding this thread:

https://www.physicsforums.com/showthread.php?t=3622"

Specifically, towards the end of the thread, the asker states (in regards to the union notation originally cited):

"...if we say that x is an element of the union of those sets, then we know x is an element of at least one of those sets. "

I thought the "or" conditional of the union meant that one (and only one) match occurs for x for the notation to be true. I could be wrong...:biggrin:
 
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Nope. "Or" always means non-exclusive or.
 
Got it, thanks...
 

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