Zusammenfassung der Ressource
Set Notation
- set notation:
- a collection of things
- each item in a set is
called an “element”
or member
- written in curly
brackets { }
- soccer = {alex,
casey, drew}
tennis = {drew,
jade, hunter}
- soccer u tennis = {alex,
casey, drew, jade,
hunter}
- interval notation
- ( ] → not including integer,
is including integer
- ( ) → not including
integer
- [ ] → is including integer
- different notations:
- numbers
- N - natural
numbers
- Q - rational numbers
- R - all
rational/irrational
numbers
- Z - integers
- unions, elements,
subsets
- unions
- ∪ -
union
- ∩ intersection
- elements
- ∅ -null set, no
elements
- ∈ - is an
element of
- ∉ - belongs to
- subsets:
- ⊂ - is a proper
subset
- ⊄ - is not a
proper
subset
- ⊆ - is a subset
- ⊊ - is not a subset
- extras:
- ∶ and| - such
that
- ∴ -
therefore
- ∋ - contains
- ∀ - for
all
- # -order or
cardinality of a
set
- ∃ - there
exists
- A' or A∁ -
complement of
A
- number lines:
- o → hollow circle =
doesn’t include the
integer
- • → filled in circle =
includes integer
- divide or multiply
with - = flip the sign
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