## What is logically equivalent to P → Q?

P→Q is logically equivalent to ¬P∨Q. … Example: “If a number is a multiple of 4, then it is even” is equivalent to, “a number is not a multiple of 4 or (else) it is even.”

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

No, compare (p⟹p)⟹r, which is equivalent to r, and p⟹(p⟹r), which is equivalent to p⟹r. It is not. Suppose p, q, r are false. Then p→q and q→r are true, so (p→q)→r is false and p→(q→r) is true.

## Are the statements P → Q ∨ R and P → Q ∨ P → are logically equivalent?

1.3. 24 Show that (p → q) ∨ (p → r) and p → (q ∨ r) are logically equivalent. By the definition of conditional statements on page 6, using the Com- mutativity Law, the hypothesis is equivalent to (q ∨ ¬p) ∨ (¬p ∨ r). … This means that the conditional from the second-to-last column the last column is always true (T).

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

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.

## Is P → Q ∨ q → p a tautology?

Example: The proposition p ∨ ¬p is a tautology. 2. A proposition is said to be a contradiction if its truth value is F for any assignment of truth values to its components. … A proposition of the form “if p then q” or “p implies q”, represented “p → q” is called a conditional proposition.

## Is P → Q ∧ Q → P logically equivalent to P → Q ∨ Q ↔ P?

Look at the following two compound propositions: p → q and q ∨ ¬p. (p → q) and (q ∨ ¬p) are logically equivalent. So (p → q) ↔ (q ∨ ¬p) is a tautology. Thus: (p → q)≡ (q ∨ ¬p).

## What is the truth value of ∼ P ∨ Q ∧ P?

So because we don’t have statements on either side of the “and” symbol that are both true, the statment ~p∧q is false. So ~p∧q=F. Now that we know the truth value of everything in the parintheses (~p∧q), we can join this statement with ∨p to give us the final statement (~p∧q)∨p.

Truth Tables.
p q p∧q
T F F
F T F
F F F

## Is logically equivalent to?

Two expressions are logically equivalent provided that they have the same truth value for all possible combinations of truth values for all variables appearing in the two expressions. In this case, we write X≡Y and say that X and Y are logically equivalent.

## Is P → Q → P → Q → QA tautology Why or why not?

[p∧(p→q)]→q ≡ F is not true. Therefore [p∧(p→q)]→q is tautology.

## Are the statements P ∧ Q ∨ R and P ∧ Q ∨ R logically equivalent?

This particular equivalence is known as De Morgan’s Law. Since columns corresponding to p∨(q∧r) and (p∨q)∧(p∨r) match, the propositions are logically equivalent. This particular equivalence is known as the Distributive Law.

## Is P -> Q equivalent to Q -> p?

The conditional of q by p is “If p then q” or “p implies q” and is denoted by p q. It is false when p is true and q is false; otherwise it is true. … Suppose a conditional statement of the form “If p then q” is given. The converse is “If q then p.” Symbolically, the converse of p q is q p.

## 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.

## Which of the following is logically equivalent to if/p then not q?

If p, then not q” is equivalent to “No p are q.” Example: “If something is a poodle, then it is a dog” is a round-about way of saying “All poodles are dogs.

## What is the negation of the statement P → Q ∨ R?

q ∨ r → pD. P ∧∼ q ∧∼ r.

## Which is the inverse of P → Q?

The inverse of p → q is ¬p → ¬q. If p and q are propositions, the biconditional “p if and only if q,” denoted by p ↔ q, is true if both p and q have the same truth values and is false if p and q have opposite truth values. The words if and only if are sometimes abbreviated iff.

## Which statement is denoted by if not p then not q?

Comparisons
name form description
implication if P then Q first statement implies truth of second
inverse if not P then not Q negation of both statements
converse if Q then P reversal of both statements
contrapositive if not Q then not P reversal and negation of both statements

## What does P only if Q mean?

Only if introduces a necessary condition: P only if Q means that the truth of Q is necessary, or required, in order for P to be true. That is, P only if Q rules out just one possibility: that P is true and Q is false.

## Is contrapositive the same as Contraposition?

As nouns the difference between contrapositive and contraposition. is that contrapositive is (logic) the inverse of the converse of a given proposition while contraposition is (logic) the statement of the form “if not q then not p”, given the statement “if p then q”.

## When the statements p and q both are true then the value of the statement P → Q ∧ Q is?

This has some significance in logic because if two propositions have the same truth table they are in a logical sense equal to each other – and we say that they are logically equivalent. So: ¬p∨(p∧q)≡p→q, or “Not p or (p and q) is equivalent to if p then q.”

Logically Equivalent Statements.
p q p→q
F F T
Mar 7, 2021

## What are logically equivalent statements?

Logical Equivalence. Definition. Two statement forms are called logically equivalent if, and only if, they have identical truth values for each possible substitution for their. statement variables.