Answer:
OPTION B
OPTION D
Step-by-step explanation:
An element in the domain should be mapped to exactly one element on the co-domain. Also, every element in the domain should be mapped to an element in the co-domain.
These two conditions are satisfied to call a relation, a function.
Two different elements in the domain can be mapped to the same element in the co-domain. But the same element in the domain cannot be mapped to two different elements in the co-domain.
A) {(3,7), (3,6), (5,4), (4,7)}
Here, the element '3' in the domain is mapped to two elements 7 and 6. So, it is not a function.
B) {(1,5), (3,5), (4, 6), (6,4)}
This is a function because all the elements in the domain have a unique image in the co-domain. So, this is a function.
C) {(2,3), (4,2), (4,6), (6,4)}
Here, the element '4' in the domain is again mapped to two different elements. Hence, it cannot be a function.
D) {(0,4), (3,2), (4,2), (6,5)}
This is again a function. Because the domain is mapped to unique elements. So, this is a function.
