Determine the negation of the expression

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The negation of the expression "p -> q ^ r" can be determined using logical equivalences. The correct negation is "-p OR -q OR -r". This follows from the understanding that the conditional statement is false only when the antecedent (p) is true and the consequent (q ^ r) is false. The discussion emphasizes the importance of using truth tables to validate the logical transformations applied to the expression.

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The question states:

Determine the negation of the expression.

p -> q ^ r.

I am having difficulty finding the negation. Below are the steps I have taken in an attempt to come to the solution.

The - symbol will be the negate symbol.

p -> q ^ r

(-p OR q) ^ r

-(-p OR q) ^ r

(p ^ -q) ^ r

-((p ^ -q) ^ r)

-p OR - r OR q

-(p ^ r) OR q

I feel like I am going in circles. I have made truth tables to compare but have had no luck. Please any advise would be appreciated.
 
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If you look at a truth table for a conditional statement such as [itex]P\rightarrow Q[/itex], you should find that the only time this statement is rendered false is if the antecedent (the first part, [itex]P[/itex]) is true and the consequent (the second part, [itex]Q[/itex]) is false.

So, what does that tell you about your problem? Keep the antecedent as it is, and negate the consequent, [itex](Q\wedge R)[/itex].
 


ironspud said:
If you look at a truth table for a conditional statement such as [itex]P\rightarrow Q[/itex], you should find that the only time this statement is rendered false is if the antecedent (the first part, [itex]P[/itex]) is true and the consequent (the second part, [itex]Q[/itex]) is false.

So, what does that tell you about your problem? Keep the antecedent as it is, and negate the consequent, [itex](Q\wedge R)[/itex].

Thank you!
 

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