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Diffstat (limited to 'set-theory.html.markdown')
| -rw-r--r-- | set-theory.html.markdown | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/set-theory.html.markdown b/set-theory.html.markdown index d55ab7d5..144b4bbf 100644 --- a/set-theory.html.markdown +++ b/set-theory.html.markdown @@ -2,7 +2,9 @@ category: Algorithms & Data Structures name: Set theory contributors: + - ["Andrew Ryan Davis", "https://github.com/AndrewDavis1191"] --- + Set theory is a branch of mathematics that studies sets, their operations, and their properties. * A set is a collection of disjoint items. @@ -17,7 +19,7 @@ Set theory is a branch of mathematics that studies sets, their operations, and t * the cross operator, `×`, means "the Cartesian product of". ### Qualifiers -* the colon qualifier, `:`, means "such that"; +* the colon, `:`, or the vertical bar `|` qualifiers are interchangeable and mean "such that"; * the membership qualifier, `∈`, means "belongs to"; * the subset qualifier, `⊆`, means "is a subset of"; * the proper subset qualifier, `⊂`, means "is a subset of but is not equal to". @@ -59,7 +61,7 @@ Long lists may be shortened with ellipses as long as the context is clear. For e Set builder notation is a more descriptive way of constructing a set. It relies on a _subject_ and a _predicate_ such that `S = { subject : predicate }`. For example, ``` -A = { x : x is a vowel } = { a, e, i, o, u, y} +A = { x : x is a vowel } = { a, e, i, o, u } B = { x : x ∈ N, x < 10 } = { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 } C = { x : x = 2k, k ∈ N } = { 0, 2, 4, 6, 8, ... } ``` |