Question

Let `A={-1,0,1,2}andB={2,3,4,5}`. Find which of the following are functions from A to B. Given reason.
(i) `f={(-1,2),(-1,3),(0,4),(1,5)}`
(ii) `g={(0 ,2),(1,3),(2,4)}`
(iii) `h={(-1,2),(0,3),(1,4),(2,5)}`

Answer 1

Correct Answer - (i) No , since one element, namely -1, has two different images.
(ii) No since dom `(g)neA`.
(iii) Yes since, each element in A has a unique image in B.
(i) No, since two different ordered pairs (-1,2) and (-1,3) have the same first coordinate.
(ii) N0, since dom `(g)={0,1,2}neA`.
(iii) Yes, dom (h) = A and no two different ordered pairs have the same first coordinate.