Question

Let A = {1, 2, 3}, B = {4, 5, 6, 7} and let f = {(1, 4), (2, 5), (3, 6)} be a function from A to B. State whether f is one-one or not.

Answer 1

f is one-one because

f (1) = 4 ; 

f (2) = 5 ; 

f (3) = 6

i.e., no two elements of A have same f image.