Discrete Maths Chapter 2: Graphs and Networks Lesson 2: Hello Mr Euler…

14
Discrete Maths Chapter 2: Graphs and Networks Lesson 2: Hello Mr Euler…

Transcript of Discrete Maths Chapter 2: Graphs and Networks Lesson 2: Hello Mr Euler…

Page 1: Discrete Maths Chapter 2: Graphs and Networks Lesson 2: Hello Mr Euler…

Discrete Maths

Chapter 2: Graphs and Networks

Lesson 2: Hello Mr Euler…

Page 2: Discrete Maths Chapter 2: Graphs and Networks Lesson 2: Hello Mr Euler…

Where graph theory came from…

Page 4: Discrete Maths Chapter 2: Graphs and Networks Lesson 2: Hello Mr Euler…
Page 5: Discrete Maths Chapter 2: Graphs and Networks Lesson 2: Hello Mr Euler…

Let’s learn some definitions…

Page 6: Discrete Maths Chapter 2: Graphs and Networks Lesson 2: Hello Mr Euler…

Trail (or route)

Page 7: Discrete Maths Chapter 2: Graphs and Networks Lesson 2: Hello Mr Euler…

Closed Trail

Page 8: Discrete Maths Chapter 2: Graphs and Networks Lesson 2: Hello Mr Euler…

Path

Page 9: Discrete Maths Chapter 2: Graphs and Networks Lesson 2: Hello Mr Euler…

Cycle

Page 10: Discrete Maths Chapter 2: Graphs and Networks Lesson 2: Hello Mr Euler…

Order

Page 11: Discrete Maths Chapter 2: Graphs and Networks Lesson 2: Hello Mr Euler…

Connected Graph

Page 12: Discrete Maths Chapter 2: Graphs and Networks Lesson 2: Hello Mr Euler…

Eulerian Graph

• CHECK: A connected graph is Eulerian if and only if every node has an even order

√ X

• A connected graph which has a closed trail containing every arc precisely once

A

B

C

DE

A

B C

D

Page 13: Discrete Maths Chapter 2: Graphs and Networks Lesson 2: Hello Mr Euler…

A wee puzzle…

F

D

B

CE

A

Page 14: Discrete Maths Chapter 2: Graphs and Networks Lesson 2: Hello Mr Euler…

Semi-Eulerian Graph

• CHECK: A connected graph is Semi-Eulerian if and only if precisely two nodes have odd order

• A graph which has a trail that is not closed that contains every arc precisely once

F

D

B

CE

A