Consider the statements: I. A ⇔  A ∨ ~ A II. A ⇔ A ∨ A III. A ∨ B ⇒ A IV. A ⇒ A ∨ B Which of the above refers to tautologies?

Consider the statements: I. A ⇔  A ∨ ~ A II. A ⇔ A ∨ A III. A ∨ B ⇒ A IV. A ⇒ A ∨ B Which of the above refers to tautologies? Correct Answer II and IV

The correct answer is option 4.

Concept:

Tautology:

 A tautology is a compound statement in Maths that always results in Truth value.

I. A ⇔  A ∨ ~ A:

False, not a tautology.

A            ~ A      A ∨ ~ A A ⇔  A ∨ ~ A
True False True True
False True True False

II. A ⇔ A ∨ A

True, The compound statement is a tautology.

A       A ∨ A A ⇔ A ∨ A
True True True
False False True

III. A ∨ B ⇒ A

False, not a tautology.

A       B      A ∨ B   A ∨ B ⇒ A
True True True True
True False True True
False True True False
False False False True

IV. A ⇒ A ∨ B

True, The compound statement is a tautology.

A       B      A ∨ B   A ⇒ A ∨ B
True True True True
True False True True
False True True True
False False False True

Hence the correct answer is II and IV.

Related Questions

The following are the conditions for selecting list of a suitable candidates to be called for interview after the written test for the recruitment is conducted/ organized for management-level persons of a multi-national company. For providing accounting services and sales the candidates must (a) be holding a graduation in basic science with 65% or above or B. E degree with 55% and above marks (b) have passed the written test with 70% or above marks (c) the age must be in the group 25 to 30 years as on 1/4/18 (d) have experience in an accounting firms for three years and diploma in accounting with 60% or above marks (e) be presently drawing CTC of 6 Lakhs per annum and above In case the applicant who satisfies all other terms above except 1) at (a) above, then be referred as Junior Accountant 2) at (d) & (e) above then be referred as Trainee-Accountant Satisfying all the above with experience of 5 years then be referred as senior-Accountant Satisfying all the above criteria (a-e) with CA/ ICWA / MBA (Finance) then be refereed as manager (Accounts) Read all the above information and answer the following question Shravani has passed H. SC with 72% of marks. She has done diploma in accountancy with 62% of marks. She was working with an organization in the field of accounting in the field of accounting from 4 years and was drawing CTC of 6.5 Lakhs presently. She is 28yrs as on July 2018. She may referred for the position of:
The following are the conditions for selecting list of a suitable candidates to be called for interview after the written test for the recruitment is conducted/ organized for management-level persons of a multi-national company. For providing accounting services and sales the candidate must (a) be holding a graduation in basic science with 65% or above or B.E degree with 55% and above marks (b) have passed the written test with 70% or above marks (c) the age must be in the group 25 to 30 yrs as on 1/4/18 (d) have experience in an accounting firms for three yrs and diploma in accounting with 60% or above marks (e) be presently drawing CTC of 6 Lakhs per annum and above In case the applicant who satisfies all other terms above except 1) at (a) above, then be referred as Junior Accountant 2) at (d) & (e) above then be referred as Trainee-Accountant Satisfying all the above with experience of 5 yrs then be referred as senior-Accountant Satisfying all the above criteria (a-e) with CA/ ICWA/ MBA (Finance) then be refereed as manager (Accounts) Read all the above information and answer the following question: Radha Mohan has done her graduation in physics with 58% of marks. She has passed the written examination with 76% of marks. She is 27 yrs as on June 2018. She has the experience in the accounting company for four years with salary of 7 Lakhs per annum. She also has passed diploma in accounting with 61% of marks. She may be referred for the position of: