R
real nums
z
all integers
q
rational nums
n
positive integers
even def
x = 2n
odd def
x = 2n + 1
same parity
both odd or even
p divides q
p | q
prime
only factors are 1 and p
composite
p has divisors
commutative
p ^ q = q ^ p
associative
parentheses can be moved
distributive
p distributes
idempotent
p ^ p = p
domination
p ^ F = F
identity
p ^ T = p
negation
p ^ ~p = F
absorption
p OR q ^ p = p
contrapositive
p ➝ q = ~q ➝ ~p
conditional as “or”
p ➝ q = ~p OR q
“and” implies “or”
tautology
A subset of B
every element of A is in B
power set of A
all subsets in A
complement of A
elements present in universal set but not A