A graph has a 3 x 3 adjacency matrix with 2's in every cell on the descending diagonal and 1's in all other cells. How many walks of length two are possible on the graph? The descending diagonal for the 3 x 3 matrix A is comprised of the cells a1,1, a2,2, a3,3.

Advanced Engineering Mathematics
10th Edition
ISBN:9780470458365
Author:Erwin Kreyszig
Publisher:Erwin Kreyszig
Chapter2: Second-order Linear Odes
Section: Chapter Questions
Problem 1RQ
icon
Related questions
Question

(Discrete Math)

 

### Understanding Walks in a Graph Using Adjacency Matrix

**Problem Statement:**

A graph has a 3x3 adjacency matrix with 2's in every cell on the descending diagonal and 1's in all other cells. How many walks of length two are possible on the graph?

The descending diagonal for the 3x3 matrix \( A \) is comprised of the cells \( a_{1,1}, a_{2,2}, a_{3,3} \).

**Explanation:**

In this problem, we are dealing with an adjacency matrix representing a graph. The entries in the matrix indicate the likelihood or capacity for moving from one vertex to another. Specifically:

- The values on the descending diagonal (i.e., from the top left to the bottom right) are 2. 
- The rest of the values are 1.

#### Adjacency Matrix \( A \):

Let's illustrate the given 3x3 adjacency matrix \( A \):

\[
A = \begin{pmatrix}
2 & 1 & 1 \\
1 & 2 & 1 \\
1 & 1 & 2 \\
\end{pmatrix}
\]

Here:
- \( a_{1,1} = 2 \)
- \( a_{2,2} = 2 \)
- \( a_{3,3} = 2 \)
- All other entries \( a_{ij} \) (where \( i \neq j \)) are 1.

#### Walks of Length Two:

A walk of length two involves moving from a starting vertex to an intermediate vertex and then to the ending vertex. Mathematically, the number of such walks can be found by squaring the adjacency matrix \( A \):

\[
A^2 = A \times A
\]

For the matrix \( A \), the product \( A^2 \) will provide the number of two-step walks between each pair of vertices. Let's compute \( A^2 \):

\[
A^2 = \begin{pmatrix}
2 & 1 & 1 \\
1 & 2 & 1 \\
1 & 1 & 2 \\
\end{pmatrix}
\times
\begin{pmatrix}
2 & 1 & 1 \\
1 & 2 & 1 \\
1 & 1 & 2 \\
\end{pmatrix}
\]

Calculating the
Transcribed Image Text:### Understanding Walks in a Graph Using Adjacency Matrix **Problem Statement:** A graph has a 3x3 adjacency matrix with 2's in every cell on the descending diagonal and 1's in all other cells. How many walks of length two are possible on the graph? The descending diagonal for the 3x3 matrix \( A \) is comprised of the cells \( a_{1,1}, a_{2,2}, a_{3,3} \). **Explanation:** In this problem, we are dealing with an adjacency matrix representing a graph. The entries in the matrix indicate the likelihood or capacity for moving from one vertex to another. Specifically: - The values on the descending diagonal (i.e., from the top left to the bottom right) are 2. - The rest of the values are 1. #### Adjacency Matrix \( A \): Let's illustrate the given 3x3 adjacency matrix \( A \): \[ A = \begin{pmatrix} 2 & 1 & 1 \\ 1 & 2 & 1 \\ 1 & 1 & 2 \\ \end{pmatrix} \] Here: - \( a_{1,1} = 2 \) - \( a_{2,2} = 2 \) - \( a_{3,3} = 2 \) - All other entries \( a_{ij} \) (where \( i \neq j \)) are 1. #### Walks of Length Two: A walk of length two involves moving from a starting vertex to an intermediate vertex and then to the ending vertex. Mathematically, the number of such walks can be found by squaring the adjacency matrix \( A \): \[ A^2 = A \times A \] For the matrix \( A \), the product \( A^2 \) will provide the number of two-step walks between each pair of vertices. Let's compute \( A^2 \): \[ A^2 = \begin{pmatrix} 2 & 1 & 1 \\ 1 & 2 & 1 \\ 1 & 1 & 2 \\ \end{pmatrix} \times \begin{pmatrix} 2 & 1 & 1 \\ 1 & 2 & 1 \\ 1 & 1 & 2 \\ \end{pmatrix} \] Calculating the
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 2 steps with 2 images

Blurred answer
Knowledge Booster
Inequality
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, advanced-math and related others by exploring similar questions and additional content below.
Similar questions
Recommended textbooks for you
Advanced Engineering Mathematics
Advanced Engineering Mathematics
Advanced Math
ISBN:
9780470458365
Author:
Erwin Kreyszig
Publisher:
Wiley, John & Sons, Incorporated
Numerical Methods for Engineers
Numerical Methods for Engineers
Advanced Math
ISBN:
9780073397924
Author:
Steven C. Chapra Dr., Raymond P. Canale
Publisher:
McGraw-Hill Education
Introductory Mathematics for Engineering Applicat…
Introductory Mathematics for Engineering Applicat…
Advanced Math
ISBN:
9781118141809
Author:
Nathan Klingbeil
Publisher:
WILEY
Mathematics For Machine Technology
Mathematics For Machine Technology
Advanced Math
ISBN:
9781337798310
Author:
Peterson, John.
Publisher:
Cengage Learning,
Basic Technical Mathematics
Basic Technical Mathematics
Advanced Math
ISBN:
9780134437705
Author:
Washington
Publisher:
PEARSON
Topology
Topology
Advanced Math
ISBN:
9780134689517
Author:
Munkres, James R.
Publisher:
Pearson,