Is Your Set Builder Notation Correct for Describing Pairs in Sets S and W?

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SUMMARY

The discussion centers on the correctness of set builder notation for describing pairs in sets S and W. The proposed notation, {x ∈ S : ∃y ∈ x, y ∈ W}, aims to identify pairs in S that contain at least one symbol from W. A clearer alternative is suggested: {(x, y) ∈ S | x ∈ W ∨ y ∈ W}. Additionally, the use of unions and Cartesian products is discussed, specifically (W × X) ∪ (X × W), where X is the set of all symbols and W is a subset of X.

PREREQUISITES
  • Understanding of set builder notation
  • Familiarity with tuples and pairs in set theory
  • Knowledge of unions and intersections in set operations
  • Basic comprehension of Cartesian products
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  • Explore the concept of tuples and their applications in set theory
  • Learn about unions and intersections in set operations
  • Investigate Cartesian products and their significance in mathematics
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Mathematicians, computer scientists, and students studying set theory, particularly those interested in formal notation and operations involving sets and pairs.

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Ok, I'm not very familiar with set notation. I was just wondering if the following is correct notation and means what I think:

{x\inS : \existsy\inx, y\inW}

S is a set of pairs of symbols (tuples of length 2 is the technical term I believe). W is a set of symbols.

What I want is the set of pairs in S that contain at least 1 symbol from set W.

Does my set builder notation correctly describe what I'm looking for? I don't necessarily have to use set builder notation; I just can't think of a way to describe it with unions, intersections, and quantifiers.
 
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I think it is correct, however it may become slightly clearer if you explicitly write down the pairs:

\{ (x, y) \in S \mid x \in W \vee y \in W \}

If you would like to omit the set builder notation, you could consider something like
(W \times X) \cup (X \times W)
where X is the set of all symbols (and W \subseteq X).
 
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