Truth Table Implication F0Da6F
1. **State the problem:**
We need to construct a complete truth table for the compound statement $$[(p \to q) \wedge (r \to \neg q)] \to (p \to \neg r)$$ and then classify it as a tautology, contradiction, or contingency.
2. **Recall the logical connectives and their truth values:**
- Implication: $$p \to q$$ is false only when $$p$$ is true and $$q$$ is false; otherwise true.
- Negation: $$\neg q$$ is true when $$q$$ is false, and vice versa.
- Conjunction: $$A \wedge B$$ is true only when both $$A$$ and $$B$$ are true.
- The main statement is an implication, so it is false only when the antecedent is true and the consequent is false.
3. **List all possible truth values for $$p$$, $$q$$, and $$r$$:**
There are 3 variables, so $$2^3 = 8$$ rows.
| p | q | r |
|---|---|---|
| T | T | T |
| T | T | F |
| T | F | T |
| T | F | F |
| F | T | T |
| F | T | F |
| F | F | T |
| F | F | F |
4. **Calculate intermediate components:**
- $$p \to q$$
- $$r \to \neg q$$
- $$p \to \neg r$$
- $$[(p \to q) \wedge (r \to \neg q)]$$
- Entire statement $$[(p \to q) \wedge (r \to \neg q)] \to (p \to \neg r)$$
5. **Fill the truth table:**
| p | q | r | $$p \to q$$ | $$r \to \neg q$$ | $$p \to \neg r$$ | $$[(p \to q) \wedge (r \to \neg q)]$$ | Statement |
|---|---|---|------------|----------------|----------------|------------------------------|-----------|
| T | T | T | T | F | F | F | T |
| T | T | F | T | T | T | T | T |
| T | F | T | F | T | F | F | T |
| T | F | F | F | T | T | F | T |
| F | T | T | T | F | T | F | T |
| F | T | F | T | T | T | T | T |
| F | F | T | T | T | T | T | T |
| F | F | F | T | T | T | T | T |
6. **Analyze the statement column:**
The statement is false only when the antecedent is true and the consequent is false.
From the table, the statement is true in all rows.
7. **Classification:**
Since the statement is true for all possible truth values of $$p$$, $$q$$, and $$r$$, it is a **tautology**.
8. **Logical significance:**
This tautology shows a logical relationship between the implications involving $$p$$, $$q$$, and $$r$$. It means that whenever $$p \to q$$ and $$r \to \neg q$$ are both true, it logically guarantees that $$p \to \neg r$$ is also true.
**Final answer:** The compound statement is a tautology.