# User:Murugan/tnou

 Work in progress, expect frequent changes. Help and feedback is welcome. See discussion page.

Objectives
 TO know about a modern mathematics subject In particular about graph theory

 A graph is an ordered triple (V,E,f) where V is a non-empty set,E is a set disjoint with V and fis the incidence function.
Now consider V={1,2,3,4},E={a,b,c,d,e,g} and f as follows:

f(a)= (1,2)
f(b)= (2,3)
f(c)= (3,4)
f(d)= (4,1)
f(e)= (1,3)
f(g)= (2,4)


This is a simple graph since it has no loops and multiple edges.So,

 What is a loop?

What is a loop?
What is link? To define these ,we need a few basic definitions.
The elements of V are called vertices,
The elements of V are called edges;
1,2 are called the ends of the edge a;Also we say a joints 1 and 2.
An edge with the same end vertices is called a loop and an edge with different end vertices is called a link.
What is a multiple edge?


# Assignment

 What is a graph? List needs of graph theory