Discrete Math

studied byStudied by 36 people
5.0(1)
get a hint
hint

discrete objects

1 / 61

encourage image

There's no tags or description

Looks like no one added any tags here yet for you.

62 Terms

1

discrete objects

can always be itemized/counted and measurable

New cards
2

not discrete

no gap in the contents of an object, continuous

New cards
3

N+

the set of natural numbers without zero

New cards
4

N0

set of natural numbers with zero

New cards
5

set

an unordered collection of distinct objects

New cards
6

element

each object in a set

New cards
7

belonging to

What symbol is this:

New cards
8

unordered (no order at all in a set)

distinct (no duplicate of any element)

What are the two criteria for a set?

New cards
9

the empty set (∅)

the set with no element

New cards
10

cardinality

the number of elements in S

New cards
11

cardinality

What does this denote: |S|

New cards
12

continuous

Is the set of real numbers continuous or discrete?

New cards
13

discrete

Is the set of natural numbers continuous or discrete?

New cards
14

def of set equality

A set A equals to another set B if and only if they have the same elements. ex. A = B

New cards
15

subset

A set A is a ______ of another set B if and only if every element of A is also an element of B. Denoted A ⊆ B.

New cards
16

proper subset

If A ⊆ B and A ≠ B, then A is a _______ _______ of B. Denoted A⊂B.

New cards
17

1) A set S is a subset of itself.

2) ∅ is a subset of every set.

What are the two important properties of subsets?

New cards
18

the total number of subsets of S

2*|S| denotes what?

New cards
19

superset

If A ⊆ B, B is called a __________ of A.

New cards
20

intersection

Let A and B be two sets. The _________ of A and B is the set of elements common to A and B. Denoted AB.

New cards
21

union

Let A and B be two sets. The ______ of A and B is the set of elements that belong to either A or B. Denoted AB.

New cards
22

commutativity

holds for union and intersection: states that you can switch positions of operands (A&B). Denoted AB=B∩A

New cards
23

associativity

holds for union and intersection: no matter the order of operations, the result will be the same. Denoted (AB)∩C=A∩(B∩C)

New cards
24

distributivity

Property that allows for the distribution of operations over addition or subtraction. Example: a(b + c) = ab + ac.

  • holds for union and intersection

  • C∩(A∪B) = (C∩A)∪(C∩B)

  • C∪(A∩B) = (C∪A)∩(C∪B)

New cards
25

complement, set complement

Let A be a set. The ________ of A is the set of all elements in the universal set which DO NOT belong to A. Denoted A' or A with a line over it.

New cards
26

parentheses, complement, union & intersection

What is the priority order of an expression with parentheses, union and intersection, and complement?

New cards
27
  • 0

  • infinity

  • any positive natural number

The cardinality of any set can be… (3 possibilities)

New cards
28
  • A∪B with line over whole thing = ‾A∩B

  • A∩B with line over whole thing = AB

What are the two relationships De Morgan’s Law shows?

New cards
29

set difference (A-B)

Let A and B be two sets. What is the set of all elements of A that DO NOT belong to B? What is the denotation?

New cards
30

cartesian product (AxB)

Let A and B be two sets. What is the set of all ordered pairs of the format (a,b) that satisfies a belongs to A and b belongs to B? What is the denotation?

New cards
31

|A| x |B|

How do you find the cardinality of cartesian product?

(|AxB|) = ????

New cards
32

power set

Let A be a set. What is the set of all subsets of A?

New cards
33

proposition/statement

a declarative sentence that either true or false, but not both (no questions or undefined variables, fact, no opinions)

New cards
34

atomic proposition

propositions that cannot be expressed in terms of simpler propositions (ex. Fanchao likes pizza.)

New cards
35

compound proposition

propositions are formed from existing propositions using logical operations (ex. If Fanchao is good at computer science, then he is good at programming.)

New cards
36

negation, ‾p

Let p be a proposition. What is the statement “It is not the case that p.”? What is the denotation?

New cards
37

conjunction (and)

If all are T, output is T

If one or more is F, putput if F.

given two propositions p and q, the __________ of p and q, denoted by pq. What is the truth table rule for this?

New cards
38

disjunction,

If all are F, output is F.

If one or more is T, output is T.

given two propositions p and q, the __________ of p and q, denoted by pq. What is the truth table rule for this?

New cards
39

equivalence, p≡q

Let p and q be two propositions. p and q are _________ if they have the same truth table value in EVERY possible case. What is the denotation?

New cards
40

exclusive or, p pinwheel q

Let p and q be two propositions. What is called the proposition that is true when exactly one of p and q is true and is false otherwise. What is the denotation?

New cards
41

conditional

T F, F

Every other case is true

Let p and q be two propositions. The ___________ statement is the proposition “if p, then q”. What is the truth table rule for this?

New cards
42

compound conditional

In a conditional statement, p→q, if p and q are compound propositions, then p→q is a ___________ _________ statement.

New cards
43

converse (switch)

Given a conditional statements, p→q, the ___________ of this conditional statements is q→p.

New cards
44

inverse (negate)

Given a conditional statements, p→q, the inverse of this conditional statements is -p→-q.

New cards
45

contrapositive (switch and negate)

Given a conditional statements, p→q, the ___________ of this conditional statement is -q→-p.

New cards
46

biconditional

Let p and q be two propositions. The ______________ statement (pq) is the proposition “p if and only if q.” pq is true when p and q have the same truth value, and false otherwise.

New cards
47

tautology

a compound proposition that is always true (every case in the truth table is true)

New cards
48

contradiction

a compound proposition that is always false (every case in the truth table is false)

New cards
49

contingency

a compound proposition that is neither a tautology nor a contradiction (most propositions are these)

New cards
50

satisfiable

a compound proposition is __________ if there is an assignment of truth variable (i.e. inputs) that makes it true

(some cases and true and some are false OR all cases are true)

New cards
51

argument

a sequence of propositions (P1, P2,…,Pn, C.) The final proposition is called the conclusion. All the statements in this sentence except the conclusion are called premises.

(P1∧P2∧…∧Pn→C)

New cards
52

valid

An argument is _______ if and only if all the premises being true forces the conclusion to be true. In other words, it is impossible for all the premises to be true and the conclusion to be false.

New cards
53

sound

An argument is __________ if and only if it is valid and contains only true premises.

New cards
54

statement

quantifier + variable + predicate

New cards
55

variable

a symbol that represents a subject/object

New cards
56

quantifier

called the universal quantifier, means “for all,” and , called the existential qualifier, means “there exists at least one”

New cards
57

predicate

a symbol represents a description of a subject/object or relation between subjects/objects

New cards
58

1) Change ∀ to ∃, or change ∃ to ∀.

2) Negate the predicate.

How do you negate statements?

New cards
59

conjunction, disjunction

ex. ∀x [P(x)∧Q(x)] = [∀xPx]∧[∀xQx]

∀ can distribute over a _______, but not over a ____________.

New cards
60

disjunction, conjunction

ex. ∃x [P(x)∨Q(x)] = [∃xPx]∨[∃xQx]

∃ can distribute over a _________, but not over a ________.

New cards
61

domain of a variable

the set from which a variable takes values

ex. All students of MU like pizza. (______ is all students of MU.)

New cards
62

domain

Whenever a variable is used, its ______ must be clarified.

New cards

Explore top notes

note Note
studied byStudied by 80 people
Updated ... ago
4.5 Stars(4)
note Note
studied byStudied by 6 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 17 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 9 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 166 people
Updated ... ago
5.0 Stars(3)
note Note
studied byStudied by 7 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 18 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 118 people
Updated ... ago
5.0 Stars(4)

Explore top flashcards

flashcards Flashcard175 terms
studied byStudied by 16 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard66 terms
studied byStudied by 11 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard30 terms
studied byStudied by 18 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard174 terms
studied byStudied by 4 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard35 terms
studied byStudied by 9 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard68 terms
studied byStudied by 6 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard57 terms
studied byStudied by 27 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard242 terms
studied byStudied by 32 people
Updated ... ago
5.0 Stars(1)