Validity of a Statement
Validity of a Statement: Overview
This topic covers concepts such as Validity of Statements, Direct Method for Validity of a Statement, Contrapositive Method for Validity of a Statement, Contradiction Method for Validity of a Statement, etc.
Important Questions on Validity of a Statement
Contrapositive of statement pattern is

Which of the following Boolean expression is a tautology?

Let and be any two propositions.
Statement I: is a tautology.
Statement II: is a fallacy.



Which of the following statement is a tautology?

Let and be two statements, then is?

Which of the following statement is a tautology

The contrapositive of is


Which one of the following is a tautology?

Prove by the method of contradiction that each of the numbers given below is an irrational number.

Prove by the method of contradiction that each of the numbers given below is an irrational number.

Prove by the method of contradiction that each of the numbers given below is an irrational number.

Prove by the method of contradiction that each of the numbers given below is an irrational number.

Prove by the method of contradiction that each of the numbers given below is an irrational number.

Prove by the method contradiction that the product of a rational number and an irrational number is an irrational number.

Check whether the statement given below is true by the method of contradiction.
‘For a real number n, if then .’

Prove that the statement ‘For three integers if and both are divisible by then the number is also divisible by ’, is true by direct method, method of contrapositive and method of contradiction.

If * is such a real number that , then . Apply direct method, method of contradiction method of contrapositive to prove that the above statement is true.
