Question

Let A = {1,2, 3} , B = {4,5,6,7} and f = {(1, 4),(2,5),(3,6)} be a function from A to B. Identify the type of function.

• A. Onto function
• B. One-one
• C. Bijection
• D. Many – one function

Answer 1

The correct option is B One-one

Given: A = {1,2, 3} , B = {4,5,6,7} and f = {(1, 4),(2,5),(3,6)}
Then 'f' is a function from A to B and for different elements in A, there are different images in B.
Hence, 'f' is one–one function.

Note: The element 7 in the co-domain does not have any pre-image in the domain. Hence, 'f' is not onto.

A function is bijection if it is both one-one and onto. Here, since 'f' is not onto so it cannot be bijection.