1.2 Flashcards
Sets
Well-defined collection of objects
does order play a part in sets
NO
Can you have a set of sets?
YES
Null Set
an empty set
Null Set Notation
0 with a line through it. NOT {0}
Disjointed sets
Sets that have NOTHING in common
{} name
braces
Subset
if every element in set A is contained in set B, then A is as subset of B
Subset notation
A <= B
Proper subset
Subset, but there is at least one element in B that is not contained in A.
Proper subset notation
A < B
Complement
everything NOT in that set
Universal set
Everything imaginable denoted U
Subset rules
The null set is a subset of every set
a set is a subset of itself
ETA
number of elements in a set
ETA notation
n(c)
subsets formula
set has N elements, then that set has 2^N subsets
Set-roster notation
{(1,3),(2,5),(4,3)}
Contained in vs member of
a number is a member of said set, yet a set of that number is contained in the larger set.
Prime number
Whole number that cannot be divided by any number other than one and itself
Perfect Number
A positive integer whose sum of divisibles equals the number itself
ex. 1 + 2 + 3 = 6
