0The function is nothing but the relation between inputs to the possible outputs, where each input is related to precisely one output.
There are various type of function
1)identity function
2)Constant function
3)polynomial function
4)Rational Function
5)Modulus function
6)Signum Function
A function f:x→y is defined to be a One-one or injective function if images of a distinct element of X under f are distinct
for every x1 and x2 ∈ X f(x1)=f(x2)
implies x1=x2
otherwise, function f is called many-one
A function f:x→y is defined to be an On-to or surjective function
if every element of Y is an image of some element of X under function f
for every y∈Y,there exist an element x in X such that f(x)=y
A function f:x→y is said to be one-one and onto (or bijective), if f is both one-one and onto.
