Math Problem Statement

Question 5 (1 point)

p → q

¬ (p ∨ q)

¬ q ↔ ¬ p

Every proposition in the above list is True when

Question 5 options:

None of the above

Both p and q are True

p is True and q is False

p is False and q is True

Both p and q are False

Solution

To determine when all the propositions in the list are true, we need to evaluate each one based on different truth values of pp and qq. The propositions given are:

  1. pqp \rightarrow q
  2. ¬(pq)\neg(p \vee q)
  3. ¬q¬p\neg q \leftrightarrow \neg p

Let's go step-by-step for each proposition:

Proposition 1: pqp \rightarrow q (Implication)

This means "if pp, then qq." It's false only when pp is true and qq is false. In all other cases, it is true.

Proposition 2: ¬(pq)\neg(p \vee q) (Negation of OR)

This is equivalent to ¬p¬q\neg p \wedge \neg q (De Morgan's Law). It means that both pp and qq must be false for the proposition to be true.

Proposition 3: ¬q¬p\neg q \leftrightarrow \neg p (Biconditional)

This is true when ¬q\neg q and ¬p\neg p have the same truth values. In other words, it is true if both pp and qq are either true together or false together.

Evaluating each case:

ppqqpqp \rightarrow q¬(pq)\neg(p \vee q)¬q¬p\neg q \leftrightarrow \neg pAll true?
TTTFTNo
TFFFFNo
FTTFFNo
FFTTTYes

Conclusion:

All three propositions are true only when both pp and qq are false.

Thus, the correct answer is:

  • Both pp and qq are False.

Would you like further details or have any questions? Here are five related questions for exploration:

  1. How does the truth table for pqp \rightarrow q differ from pqp \leftrightarrow q?
  2. Can you provide an example where pqp \vee q is false?
  3. How does De Morgan’s law help simplify logical expressions?
  4. What are the possible truth values of a biconditional statement pqp \leftrightarrow q?
  5. How do you interpret negation in logic?

Tip: To solve complex logical propositions, truth tables can simplify the analysis of each possible case.

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Math Problem Analysis

Mathematical Concepts

Logic
Propositional Logic
Truth Tables
Logical Connectives

Formulas

Implication: p → q
Negation of OR: ¬(p ∨ q) ≡ ¬p ∧ ¬q
Biconditional: ¬q ↔ ¬p

Theorems

De Morgan’s Law
Truth Table Evaluation
Logical Equivalence

Suitable Grade Level

Grades 10-12