

Last updated at Jan. 28, 2020 by Teachoo
Transcript
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 2 Deleted for CBSE Board 2021 Exams only
Misc 3 Important Deleted for CBSE Board 2021 Exams only
Misc. 4 Important
Misc 5
Misc 6 Deleted for CBSE Board 2021 Exams only
Misc 7 Deleted for CBSE Board 2021 Exams only
Misc. 8 Important
Misc 9 Important Deleted for CBSE Board 2021 Exams only
Misc 10 Important
Misc 11 Important Deleted for CBSE Board 2021 Exams only
Misc 12 Deleted for CBSE Board 2021 Exams only
Misc 13 Important Deleted for CBSE Board 2021 Exams only
Misc 14 Important Deleted for CBSE Board 2021 Exams only
Misc 15
Misc 16 Important You are here
Misc 17 Important
Misc 18
Misc, 19 Important Deleted for CBSE Board 2021 Exams only
About the Author