MATH Flashcards
A collection of points called vertices or
nodes and line segments or curves called edges
that connect the vertices
GRAPH
is an edge connecting a vertex to itself.
a special type of edge.
β It can only have one vertex.
LOOP
A complete graph is a graph that has an edge
connecting every pair of vertices.
COMPLETE GRAPH
Two vertices are adjacent if there is an edge joining
them
ADJACENT (VERTICES)
Graphs are considered ________if they have the
same vertices connected in the same way
equivalent
an alternating sequence of vertices and
edges. It can be seen as a trip from one vertex to
another using the edges of a graph.
β If a path begins and ends with the same vertex,
it is a closed path or a circuit or cycle.
PATH
A graph is connected if for any two ________, there
is at least one path that joins them. A _________ is an
edge that when you remove makes the graph
disconnected.
Vertices
Bridge
The degree of a vertex is the number of edges
attached to it.
DEGREE.
The idea is to color the vertices or
edges of a graph in such a way that adjacent
vertices or concurrent edges are given different
colors.
GRAPH COLORING
The smallest number of colors required to color the
vertices of a graph.
CHROMATIC NUMBER OF THE GRAPH
FINDING THE TOTAL NUMBER OF EDGES IN A
COMPLETE GRAPH
ππ =1/2 x π(π β 1)
A graph is 2-colorable if and only if it has _________
that consist of an ____number of vertices
No circuits
Odd
A map can be represented by a graph with the
different regions as vertices. Two regions are
adjacent if they share part of their boundaries.
MAP COLORING
β A path that passes through every edge exactly
once only
β A path that contains all the edges of the graph
β A graph has an Euler path if and only if no
more than two of its vertices have odd degree
EULER PATH
a graph is a closed path that
contains all the edges of the graph. A graph that
has an Euler circuit is called Eulerian.
EULER CIRCUIT
If all vertices are even, the graph has at least
__________
If exactly two vertices are odd, the graph has
_________
If there are more than two odd vertices, the
graph has __________
1.) one Euler circuit
2.) no Euler circuits but at least one Euler path
3.) no Euler path and no Euler circuits