The truth table shows that the biconditional is true when its two components have the same truth value and that otherwise it is false. These results are required by the fact that **P≡Q is simply a shorter way of writing (P⊃Q)∧(Q⊃P)**.

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## Is a biconditional true if both statements are false?

**The biconditional statement p⇔q is true when both p and q have the same truth value, and is false otherwise**. A biconditional statement is often used in defining a notation or a mathematical concept.

## What makes a biconditional statement true?

It is a combination of two conditional statements, “if two line segments are congruent then they are of equal length” and “if two line segments are of equal length then they are congruent”. A biconditional is true **if and only if both the conditionals are true**.

## What are the two requirements for writing a biconditional statement?

‘ Biconditional statements are true statements that combine the hypothesis and the conclusion with the key words ‘**if and only if**. ‘ For example, the statement will take this form: (hypothesis) if and only if (conclusion). We could also write it this way: (conclusion) if and only if (hypothesis).

## How do you prove a biconditional statement?

Proofs of Biconditional Statements

**(P↔Q)≡(P→Q)∧(Q→P)**. This logical equivalency suggests one method for proving a biconditional statement written in the form “P if and only if Q.” This method is to construct separate proofs of the two conditional statements P→Q and Q→P.

## How do you define a biconditional statement?

Definition: A biconditional statement is **defined to be true whenever both parts have the same truth value**. The biconditional operator is denoted by a double-headed arrow . The biconditional p q represents “p if and only if q,” where p is a hypothesis and q is a conclusion.

## What is biconditional in truth table?

A biconditional is **considered true as long as the antecedent and the consequent have the same truth value**; that is, they are either both true or both false.

## Is biconditional statement undefined?

Remember, **it is only possible to write a biconditional statement if both the statement and its converse are true**. If the statement is true, but the converse is false, then it is not possible to write the conditional statement as a biconditional statement.

## What is a conditional statement that is false but has a true inverse?

Negating both the hypothesis and conclusion of a conditional statement. For example, the inverse of “If it is raining then the grass is wet” is “If it is not raining then the grass is not wet”. Note: As in the example, **a proposition** may be true but its inverse may be false.

## When can we say that a conditional statement will be true or false?

A conditional is considered true **when the antecedent and consequent are both true or if the antecedent is false**. When the antecedent is false, the truth value of the consequent does not matter; the conditional will always be true.

## Are inverse statements always true?

If the statement is true, then the contrapositive is also logically true. **If the converse is true, then the inverse is also logically true**.

Example 1:

Statement | If two angles are congruent, then they have the same measure. |
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Inverse | If two angles are not congruent, then they do not have the same measure. |

## What is the inverse of false?

If a statement is false, then its **contrapositive** is false (and vice versa). If a statement’s inverse is true, then its converse is true (and vice versa).

## Can the converse be true and inverse be false?

**If the converse statement is true, then the inverse has to also be true, and vice versa**. Likewise, if the converse statement is false, then the inverse statement must also be false and vice versa. The logical converse and inverse of the same conditional statement are logically equivalent to each other.

## Why converse and inverse are logically equivalent?

The converse of “if p, then q” is “if q, then p.” **The inverse is logically equivalent to the converse**. The contrapositive of a conditional statement both swaps the hypothesis and the conclusion and negates both the hypothesis and the conclusion.