27 lines
653 B
Markdown
27 lines
653 B
Markdown
---
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id: 2025-12-02T10:57:00-0500
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title: 2025-12-02 10:57:??
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tags: []
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daily: "[[2025-12-02]]"
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---
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# 2025-12-02 10:57:??
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### Set Notation Example
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Let $A$ and $B$ be [[set-theory|sets]]
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sharing some but not all elements.
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* $A \cap B \neq \varnothing$:
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"The intersection of $A$ and $B$ is nonempty"
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(They share at least one element).
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* $A \not\subseteq B$:
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"$A$ is not a subset of $B$"
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($A$ has at least one element not in $B$).
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Equivalent to $A \setminus B \neq \varnothing$.
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* $B \not\subseteq A$:
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"$B$ is not a subset of $A$"
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($B$ has at least one element not in $A$).
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Equivalent to $B \setminus A \neq \varnothing$.
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