A Place for Latest Exam wise Questions, Videos, Previous Year Papers, Study Stuff for MCA Examinations - NIMCET
Previous Year Question (PYQs)
1
Which of the following relations are functions?
(i) ${(1,(a,b)),\ (2,(b,c)),\ (3,(c,a)),\ (4,(a,b))}$
(ii) ${(1,(a,b)),\ (2,(b,a)),\ (3,(c,a)),\ (1,(a,c))}$
(iii) ${(1,(a,b)),\ (2,(a,b)),\ (3,(a,b))}$
(iv) ${(1,(a,b)),\ (2,(b,c)),\ (1,(c,a))}$
Solution
A relation $R$ is a function iff every first component occurs exactly once.
(i) first components $1,2,3,4$ appear once each $\Rightarrow$ function.
(ii) $1$ appears twice $\Rightarrow$ not a function.
(iii) $1,2,3$ appear once each $\Rightarrow$ function.
(iv) $1$ appears twice $\Rightarrow$ not a function.
Online Test Series, Information About Examination, Syllabus, Notification and More.