- Constant function
A function f : A→B is called a constant function if every element of A has the same
image in B. In other words, f associates the same element b ∈^ B with each element
at a ∈^ A.
f : A→B and f(x) = x^2
- Identity function
Let A be a non-empty set. A function f : A→A is called an identity function if each
element of A is associated with itself under ‘f.’ In other words, ‘f’ is an identity
function of A if f(x) = x for each element x ∈ A.
Two sets which are tactually attractive with some elements on both may be prepared
and used for explaining all the types of functions.
Eg. :
f : A→B and f(x) = x
- Ordered pairs
Any function f : A→B can be represented as a set of ordered pairs as follows:
f = {(x, y); x ∈ A, y ∈ B}
As the child is already familiar with the idea of ordered pairs, representation of a
function in the form of an ordered pair may be easy for the child to understand.
1
2
3
1
2
3
A B
4
16
A B
