Set Theory: Is {a} a Subset of {S}?

AI Thread Summary
The discussion centers on set theory, specifically whether the set {a} is a subset of another set S. A user proposes S = {{a}, b}, asserting that {a} belongs to S but is not a subset, as subsets require elements to be directly contained within the set. Another participant clarifies that for {a} to be a subset, 'a' must be an element of S, not just {a}. The conversation highlights the distinction between belonging to a set and being a subset, emphasizing the need for correct understanding of set membership and subset definitions. The participants acknowledge the confusion and refine their reasoning regarding subsets.
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Homework Statement


I am not sure if set theory is precalc or not but here is my question.

Find a pair set such that {a} belongs to the set and {a} is not a subset of S.


The Attempt at a Solution


So I thought that a set like this would work S = {{a}, b} because {a} belongs to the set, but in order for {a} to be a subset it has to be wrapped in more brackets so {{a}} is a subset. Am I right? If not what did I state that was wrong?
 
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The example you have chosen is alright ,but the reasoning doesn't looks okay .For {a} to be a subset , 'a' should be an element of the set ,not {{a}} .For example for the set {a,b} , the subsets can be {a,b},{a},{b},ø . For set {{a},b} , the subsets can be {{a},b} , {{a}} ,{b} , ø .
 
Yea I realized my explanation was wrong but ny reasoning was the same as yours
 
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