# What is the logical law proving “if not p then q” is equivalent to “p or q”?

In propositional logic, material implicationmaterial implicationThe material conditional (also known as material implication) is an operation commonly used in logic. When the conditional symbol is interpreted as material implication, a formula is true unless is true and.

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## What is logically equivalent to if not p then q?

Contrapositive: The contrapositive of a conditional statement of the form “If p then q” is “If ~q then ~p”. Symbolically, the contrapositive of p q is ~q ~p. A conditional statement is logically equivalent to its contrapositive.

## Why is p implies q logically equivalent to not P or Q?

Given “p implies q”, there are two possibilities. We could have “p”, and therefore “q” (so q is possibility 1). Or, we could have “not p”, and therefore, we would not have q (so we could use possibility 2 as not p). Thus, “p implies q” is equivalent to “q or not p”, which is typically written as “not p or q”.

## Is P -> Q the same as not P or Q?

“p implies q”, p→q is equivalent to “q or not p”, q∨¬p. This is an inclusive or; it does not exclude the possibility that q and ¬p may be both true.

## Are P → Q and P ∨ Q logically equivalent?

They are logically equivalent. p ↔ q ≡ (p → q) ∧ (q → p) p ↔ q ≡ ¬p ↔ ¬q p ↔ q ≡ (p ∧ q) ∨ (¬p ∧ ¬q) ¬(p ↔ q) ≡ p ↔ ¬q c Xin He (University at Buffalo) CSE 191 Discrete Structures 28 / 37 Page 14 Prove equivalence By using these laws, we can prove two propositions are logical equivalent.

## How do you determine logical equivalence?

To test for logical equivalence of 2 statements, construct a truth table that includes every variable to be evaluated, and then check to see if the resulting truth values of the 2 statements are equivalent.

## Are the statements P Q and ~( Pvq equivalent?

It means that either p is false or q is false or they are both false–anyway, p and q can’t both be true at the same time. So ~(p · q) º ~p v ~q. On the other hand, ~(p v q) means it’s not the case that either p or q. In other words, they ate both not true.

## What is negation Law?

Negation Law. Negation Law. In logic, negation is an operation that essentially takes a proposition p to another proposition “not p”, written as ~p, which is interpreted intuitively as being true when p is false and false when p is true.

## How do you determine if two statements are logically equivalent?

Logical equivalence occurs when two statements have the same truth value. This means that one statement can be true in its own context, and the second statement can also be true in its own context, they just both have to have the same meaning.

## What is logical equivalence examples?

Now, consider the following statement: If Ryan gets a pay raise, then he will take Allison to dinner. This means we can also say that If Ryan does not take Allison to dinner, then he did not get a pay raise is logically equivalent.

## What does logically equivalent mean in logic?

Logical equivalence is a type of relationship between two statements or sentences in propositional logic or Boolean algebra. The relation translates verbally into “if and only if” and is symbolized by a double-lined, double arrow pointing to the left and right ( ).

## Which of the following is logically equivalent to ~[~ P → q *?

Solution: (4) ~ p ˄ ~ q