For example f ( x ) = 3 x, x Î { 1, 2, 3 }
 Many  One function
A function f : A ® B is many  one if two or more elements of A have the same in B.
For example f ( x ) = x_{2}, x Î { 1, 1, 2, 2 }.
 Onto function ( Surjection )
A function f : A ® B is called an onto function if every element of B is an of some element of A i.e. the codomain = range.
(a) Oneone onto :Oneone onto also known as
(Bijection )bijective mapping or bijective;function.
(b) Manyone onto :
 Into function
A function f : A ® B is called an into function if the co domain ¹ range

Index
6.1 Relations
6.2 Functions 6.3 Variation
Chapter 7
