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Last updated at Jan. 28, 2020 by Teachoo

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Misc 16 Let A = {1, 2, 3}. Then number of relations containing (1, 2) and (1, 3) which are reflexive and symmetric but not transitive is (A) 1 (B) 2 (C) 3 (D) 4 Total possible pairs = { (1, 1) , (1, 2), (1, 3), (2, 1) , (2, 2), (2, 3), (3, 1) , (3, 2), (3, 3) } Total possible pairs = { (1, 1) , (1, 2), (1, 3), (2, 1) , (2, 2), (2, 3), (3, 1) , (3, 2), (3, 3) } Reflexive means (a, a) should be in relation . So, (1, 1) , (2, 2) , (3, 3) should be in a relation Symmetric means if (a, b) is in relation, then (b, a) should be in relation . So, since (1, 2) is in relation, (2, 1) should be in relation & since (1, 3) is in relation, (3, 1) should be in relation Transitive means if (a, b) is in relation, & (b, c) is in relation, then (a, c) is in relation We need relation which is not transitive. So, we cannot add any more pair in the relation. If we add (2, 3), we need to add (3, 2) for symmetric, but it would become transitive then Relation R1 = { So, there is only 1 possible relation Correct answer is A.

Miscellaneous

Misc 1
Not in Syllabus - CBSE Exams 2021

Misc 2 Not in Syllabus - CBSE Exams 2021

Misc 3 Important Not in Syllabus - CBSE Exams 2021

Misc. 4 Important

Misc 5

Misc 6 Not in Syllabus - CBSE Exams 2021

Misc 7 Not in Syllabus - CBSE Exams 2021

Misc. 8 Important

Misc 9 Important Not in Syllabus - CBSE Exams 2021

Misc 10 Important

Misc 11 Important Not in Syllabus - CBSE Exams 2021

Misc 12 Not in Syllabus - CBSE Exams 2021

Misc 13 Important Not in Syllabus - CBSE Exams 2021

Misc 14 Important Not in Syllabus - CBSE Exams 2021

Misc 15

Misc 16 Important You are here

Misc 17 Important

Misc 18

Misc, 19 Important Not in Syllabus - CBSE Exams 2021

Chapter 1 Class 12 Relation and Functions

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About the Author

Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.