Logic Flashcards

1
Q

is the study of methods of reasoning or argumentation. It is also a science or study of how to evaluate arguments and reasoning.

A

Logic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

is a declarative sentence which is true or false, but not both.

A

proposition or statement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

one and only one of which is assignable to any given statement is called the

A

‘truth value’ of that statement.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

are used to represent propositions, usually denoted by small letters, such as p, q, r, s and t.

A

Propositional variables

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

contains one or more variables, that is, it is either true or false depending on the value of the placeholder.

A

open sentence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

on the other hand, is a mathematical sentence that is known to be either true or false.

A

closed sentence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

is a proposition formed from simple propositions using logical connectors or some combinations of logical connectors.

A

compound proposition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

are words, expressions, or phrases that point out the number of elements that a statement relates to

A

Quantifiers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

There are two types of quantifiers:

A

universal quantifier and existential quantifier.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

denoted by ∀, refers to the phrase “for all” or “for every” or “for each”. It asserts that the formula for any value of 𝑦 (the value as being taken from some given universe or the set of objects of interest).

A

universal quantifier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

denoted by ∃, refers to the phrase “there exists” or “for at least one” or “for some”. It asserts that the formula holds for at least one value of 𝑦.

A

existential quantifier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Give any proposition “p”, its opposite is a statement “not p” referred to as the “negation” of the given proposition “p”. Likewise, “p” is the negation of “not p”.
Definition: If p is true, then ~p is false; and if p is false, then ~p is true.

A

Negation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

A compound statement formed by connecting two statements with the word “and” is called a ___. In symbols, it is written as “p ∧ q” which is read as “p and q”.
Definition: If p and q are true, then p ∧ q is true; otherwise p ∧ q is false.

A

Conjunctions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

A compound statement formed by connecting two statements with the word “or” is called ???. Symbolically, “p ∨ q” which is read as “p or q”.
Definition: If p and q are false, then p ∨ q is false; otherwise p ∨ q is true.

A

Disjunctions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

A compound statement formed by connecting two statements with the words “if…then” is called a ????. Symbolically, “p → q” which is read as “If p, then q” or “p implies q”.
The statement p is called antecedent and q is the consequent.

A

Conditional

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

A compound statement formed by connecting two statements with the word “or” is called ???. Symbolically, “p ⨁ q” which is read as “p exclusive or q”.

Definition: Proposition is true when exactly one of its proposition is true and the other one is false.

A

exclusive or.

17
Q

A compound statement formed by connecting two statements with the words “if and only if” is called a ???. Symbolically, “p ↔ q” which read as “p if and only if q”.

A

Biconditional and Equivalent Statements

18
Q

The three important classes of compound statements namely ?,? and ?.

A

tautology, contradiction and contingency.

19
Q

A compound statement is a ? if its truth value is always T, regardless of the truth values of the statements of which it is composed.

Example:
The statement 𝑝→(𝑝∨𝑞) is a tautology.

A

tautology

20
Q

A compound statement is a ? if is truth value is always F, regardless of the truth values of its variables.

Example:
The statement (𝑝∧~𝑞)∧(𝑝∧𝑞) is a contradiction.
A

contradiction

21
Q

A compound statement is a ? if it is neither tautology nor contradiction.

Example:
The statement ((𝑝→𝑞)∧𝑞)→𝑝 is a contingency.
A

contingency

22
Q

stopped at page 33. continue pg. 34 skip this muna

A

stopped at page 33. continue pg. 34 skip this muna