Ch. 3. Functions - 2 (Kinds of Functions)

Kinds of Functions

One-One function

A function f:A→B is said to be a one-one function if different elements of A have different images in B.

Many-One function

A function f:A→B is said to be many-one function if two or more elements of set A have the same image in B.

Onto function

A function f:A→B is said to be an onto function if every element of B is the f image of some element of A.

Range of is the codomain of f. Codomain of f is B.

Into function

A function f:A→B is said to be an into function if there exists an element in B having no pre-image in A.

One-one onto function

A function which is one-one as well as onto function.