Question
If p (q r) is false, then the truth values of p, q, r are respectively :-
Options
Solution
Key Concepts and Formulas
- Implication: The statement (p implies q) is false only when p is true and q is false.
- Disjunction: The statement (q or r) is true if either q is true, r is true, or both are true. It is false only when both q and r are false.
- Negation: The negation of a statement p, denoted by , has the opposite truth value of p. If p is true, is false, and vice versa.
Step-by-Step Solution
Step 1: Understand the given condition. We are given that is false. We need to determine the truth values of p, q, and r.
Step 2: Apply the definition of implication. The implication is false if and only if is true and is false. Therefore, we have:
Step 3: Determine the truth values of q and r. Since is false, it means that both q and r must be false. The disjunction (OR) is only false when both statements are false. Therefore:
Step 4: Summarize the truth values. We found that is true, is false, and is false.
Common Mistakes & Tips
- Remember the truth table for implication. It's crucial to know when is false.
- Understand the difference between conjunction (AND) and disjunction (OR). is only true if both q and r are true, while is false only if both q and r are false.
- When dealing with false implications, always start by making the left side true and the right side false.
Summary
We are given that is false. This occurs only when p is true and is false. For to be false, both q and r must be false. Therefore, the truth values of p, q, and r are true, false, and false, respectively.
Final Answer The final answer is \boxed{T, F, F}, which corresponds to option (B).