What is the inverse of the statement 'If p, then q'?
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If not p, then not q.
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What is the inverse of the statement 'If p, then q'?
If not p, then not q.
What is a tautology?
A compound proposition where its truth values are always true.
What is the biconditional statement of propositions p and q?
p if and only if q, denoted as p ↔ q.
What are the two proposition variables in the example?
p and q.
What does the symbol ∃ represent in logic?
The existential quantifier, denoting 'for some', 'there exist', or 'there is at least one'.
What does it mean to instantiate a variable?
To give a variable a specific value.
What is the converse of a conditional statement?
Reversing the hypothesis and the conclusion.
What are the possible classifications of a compound proposition?
Tautology, contradiction, or contingency.
When is the compound proposition p → q false?
It is false when p is true and q is false; otherwise, it is true.
Is the converse always true if the original statement is true?
No, the converse is not always true just because the original statement is true.
When is the biconditional proposition p ↔ q true?
When both p and q have the same truth values.
What is the first compound proposition to evaluate for logical equivalence?
p → q.
What is the truth value of the proposition '3 or -5 is negative'?
True (because -5 is negative).
What does the biconditional connective '↔' mean?
If or only if.
Given P(x): x - 3 > 5, what is the truth value of P(2)?
False.
How is the negation of a proposition 'p' denoted?
¬p.
What are some alternative expressions for p → q?
If p, then q; q if p; p implies q; q when p; p only if q; q is necessary for p.
What is a Compound Proposition?
A proposition formed by combining one or more atomic propositions using logical connectives.
When is the negation ¬∀x P(x) true?
When there is an x for which P(x) is false.
When is the compound proposition p ∨ q false?
It is false when both p and q are false.
What are the truth values for p ∨ q when both p and q are true?
True.
What is the definition of implication in propositional logic?
If p and q are proposition variables, the implication of p and q is 'if p, then q', denoted as p → q.
What is the truth value of the proposition 'Horses are bigger than cats'?
True or False, depending on the context.
What distinguishes an Atomic Proposition from other propositions?
Atomic propositions cannot be broken down into smaller propositions.
What is the formal name for the connective represented by '∧'?
Conjunction (And).
What is Logic?
The systematic study of the principles of valid reasoning and inference.
What is the relationship between p → q and ¬p ∨ q?
They are logically equivalent.
What is the implication connective symbol?
→ (If…., then…).
What is the truth set of a predicate P(x)?
The set of all elements of D that make P(x) true when substituted for x.
When is the exclusive or p ⊕ q true?
When exactly one of p and q is true.
What is the truth value of a true proposition?
True (T), corresponding to 1 in digital circuits.
What is the truth table for negation?
If p is True (T), ¬p is False (F); if p is False (F), ¬p is True (T).
When is the compound proposition p ∨ q true?
It is true if at least one of p or q is true.
What is an Atomic Proposition?
A proposition whose truth or falsity does not depend on any other proposition.
How is the truth set of P(x) denoted?
{ x ∈ D | P(x) }
What is the truth value of the negation of a true proposition?
False.
What is the truth table for the implication p → q?
The truth values are: T T T, T F F, F T T, F F T.
What is the truth value of a false proposition?
False (F), corresponding to 0 in digital circuits.
What is the negation of the proposition 'The integer 10 is even'?
The integer 10 is not even.
What is the negation of the statement 'There is a man taller than three meters'?
There is no man taller than three meters.
What is the universe of discourse or domain D of a predicate variable?
The set of all values that may be substituted in place of the variable.
What is the truth value of the biconditional statement when p is true and q is false?
False.
What is an existential statement?
A statement of the form '∃x ∈ D such that P(x)', meaning there exists an element x in D such that P(x) is true.
What are the terms used for p and q in the implication p → q?
p is called the antecedent (or hypothesis) and q is called the consequent (or conclusion).
What is the truth value of the proposition '√2 or π is an integer'?
False (neither √2 nor π is an integer).
What does the symbol ∀ represent in logic?
The universal quantifier, denoting 'for all', 'for each', and 'for every'.
What are De Morgan’s Laws for Quantifiers?
Rules for negating quantifier expressions, stating ¬∀x P(x) is equivalent to ∃x ¬P(x) and ¬∃x P(x) is equivalent to ∀x ¬P(x).
What is the negation of the statement 'Every student in Discrete Mathematics class has taken Mathematics Logic'?
There exists at least one student in Discrete Mathematics class who has not taken Mathematics Logic.
What is the compound proposition for part a of the example?
¬𝑝 ∨ ~𝑞
What is the exercise task related to truth tables?
Construct a truth table for the compound proposition (𝑝 ∧ 𝑞) ∨ ¬𝑟.
What symbol represents negation?
¬
When is the biconditional proposition p ↔ q false?
When p and q have opposite truth values.
What is the second compound proposition to evaluate for logical equivalence?
¬p ∨ q.
What does the symbol '∨' represent?
Disjunction (Or).
What is a Proposition?
A declarative sentence that is either true or false, but not both.
What is the exclusive or (XOR) of propositions p and q denoted as?
p ⊕ q.
Is 'Please do not fall asleep' a proposition?
No, it is a command, not a statement that can be true or false.
How do the truth values of p ⊕ q and p ↔ q relate?
They have opposite truth values.
Given P(x): x - 3 > 5, what is the truth value of P(8)?
False.
What is the correct order of operations in logic?
¬ is performed first, then ∧ and ∨, and finally → and ↔.
What is a truth table?
A table that gives the truth values of a compound proposition in terms of its component parts.
What is a Propositional Function?
A statement that contains variables and becomes a proposition when the variables are replaced with specific values.
What is the domain for Q(x): x is an animal?
{ cat, apple, computer, elephant }
What is the disjunction of two propositions p and q denoted as?
p ∨ q.
What is a predicate (or propositional function)?
A sentence that contains a finite number of predicate variables and becomes a statement when particular values are substituted for the variables.
What is the truth value of the biconditional statement when both p and q are true?
True.
What is the truth value of the proposition '3 + 3 = 5 or 1 = 1'?
True (because 1 = 1 is true).
What is an atomic proposition?
A simple statement that can be true or false, such as 'The sky is blue.'
What does p → q ↔ ¬p ∨ q signify?
It indicates that p → q is equivalent to ¬p ∨ q.
When is an existential statement defined to be true?
If and only if P(x) is true for at least one x in D.
What is the converse of the statement 'If p, then q'?
If q, then p.
What is the truth value of the proposition '5 ≤ 5'?
True.
What can override the order of operations in logical expressions?
Parentheses ( ).
What is a compound proposition?
A proposition formed by combining one or more atomic propositions.
What is a universal statement?
A statement of the form '∀x ∈ D, P(x)' means 'P(x) is true for all values of x in D'.
When is the negation ¬∃x P(x) false?
When there is an x for which P(x) is true.
What is the implication in the statement: 'If 1 + 1 = 3, then cats can fly'?
The implication is that the truth of '1 + 1 = 3' leads to the conclusion that 'cats can fly'.
Translate 'For every x, if x is a natural number, then x is an integer' into logical symbolism.
∀x (if x ∈ ℕ, then x ∈ ℤ).
Express the proposition: 'If there are no clouds in the sky, then it is not raining and the sun is shining' using p, q, r.
¬r → (¬p ∧ q).
When is an existential statement defined to be false?
If and only if P(x) is false for all x in D.
What is a simple statement in propositional logic?
A proposition represented by an atomic proposition variable.
What is the inverse of a conditional statement?
Negating both the hypothesis and the conclusion.
Given P(x): x - 3 > 5, what is the truth value of P(9)?
True.
Determine the truth value of the statement: 'The moon is square only if the sun rises in the East.'
The truth value depends on the truth of the antecedent and consequent.
When is the compound proposition p ∧ q true?
It is true when both p and q are true; otherwise, it is false.
What is a counterexample in the context of universal statements?
A value for x for which P(x) is false.
What type of statement is 'Math is fun'?
It is an opinion and not a proposition since it cannot be definitively true or false.
What is the logical relationship between the contrapositive and the original statement?
The contrapositive is logically equivalent to the original statement.
What does the expression ∀x ∃y P(x, y) mean?
For every x, there exists a y such that P(x, y) is true.
Identify the hypothesis and conclusion in the statement: 'If you place your order by 11:59pm December 21st, then we guarantee delivery by Christmas.'
Hypothesis: You place your order by 11:59pm December 21st; Conclusion: We guarantee delivery by Christmas.
What is the conjunction of two proposition variables p and q denoted as?
It is denoted as p ∧ q.
What is a contingency?
A compound proposition that is neither a tautology nor a contradiction.
What is the conjunction of the propositions 'It is snowing' and 'I am cold'?
'It is snowing and I am cold.'
Express the proposition: 'If the sun is shining or there are no clouds in the sky, then it is not raining' using p, q, r.
(q ∨ ¬r) → ¬p.
Are the converse and inverse logically equivalent?
Yes, the converse and inverse are logically equivalent to each other.
What is Q(x) in the example provided?
Q(x): x is an animal.
Is 'The sun rises in the West' a proposition?
Yes, but it is false.
What is the truth value of the proposition: 'The integer 2 is even but it is a prime number'?
False, because while 2 is even, it is not a prime number.
When is a universal statement considered true?
It is true if and only if P(x) is true for every x in D.
Can all sentences be considered propositions?
No, not all sentences are propositions; only those that are declarative and can be true or false.
What is the contrapositive of the statement 'If p, then q'?
If not q, then not p.
Translate 'Every triangle is a polygon' into logical symbolism.
∀x (if x is a triangle, then x is a polygon).
Translate 'All Sunway students are geniuses' into logical symbolism.
∀x (if x is a Sunway student, then x is a genius).
Is the inverse guaranteed by the truth of the original statement?
No, the inverse is not guaranteed by the truth of the original statement.
When is a universal statement considered false?
It is false if and only if P(x) is false for at least one x in D.
What are the truth values for conjunction summarized in the truth table?
T T T, T F F, F T F, F F F.
Express the proposition: 'If it is raining, then the sun is not shining and there are clouds in the sky' using p, q, r.
p → (¬q ∧ r).
Express the proposition: 'The sun is shining if and only if it is not raining' using p, q.
q ↔ ¬p.
What is a contradiction?
A compound proposition where its truth values are always false.
What is the contrapositive of a conditional statement?
Both reversing and negating the hypothesis and the conclusion.
How can you determine if two compound propositions P and Q are logically equivalent?
By constructing the truth table P ↔ Q or using equivalence laws.
Determine the truth value of the proposition: '3 < 5 and 5 + 6 ≠ 11'.
False, because 5 + 6 = 11.
What is the domain of R(x, y) in the given example?
Pairs (x, y) where x = 1, 2, or 3 and y = 3, 4.
How do you determine the number of possible truth values based on the number of variables?
The number of possible truth values is 2^n, where n is the number of variables.
Is the contrapositive always true if the original statement is true?
Yes, the contrapositive is always true if the original statement is true.
Determine the truth value of the proposition: '5 is positive and Kuala Lumpur is in Malaysia'.
True, both statements are correct.
What is the symbolic logic for the statement 'If it is snowing, then it is cold'?
p → q, where p is 'It is snowing' and q is 'It is cold'.
What are logical operators also known as?
Connectives.
What is the compound proposition for part b of the example?
(¬𝑝 ∨ 𝑞) ∧ (¬𝑟)
