Math Problem Statement

Directions: Type your solutions into this document and be sure to show all steps for arriving at your solution. Just giving a final number may not receive full credit. Problem 1 For parts (a) and (b), indicate if each of the two graphs are equal. Justify your answer. (a) Figure 1: Left: An undirected graph has 5 vertices. The vertices are arranged in the form of an inverted pentagon. From the top left vertex, moving clockwise, the vertices are labeled: a, b, c, d, and e. Undirected edges, line segments, are between the following vertices: a and b; a and c; b and c; c and d; e and d; and e and c. Figure 2: Right: The adjacency list representation of a graph. The list shows all the vertices, a through e, in a column from top to bottom. The adjacent vertices for each vertex in the column are placed in a row to the right of the corresponding vertex’s cell in the column. An arrow points from each cell in the column to its corresponding row on the right. Data from the list, as follows: Vertex a is adjacent to vertices b and c. Vertex b is adjacent to vertices a and c. Vertex c is adjacent to vertices a, b, d, and e. Vertex d is adjacent to vertices c and e. Vertex e is adjacent to vertices c and d.

The vertex set in both figures is: V = {a, b, c, d, e} Since there are no extra or missing vertices, this matches. • Comparing each vertex’s adjacency list with the edges in Figure 1: – Vertex a: - Adjacency List: {b, c} - Expected Edges: (a, b), (a, c) – Vertex b: - Adjacency List: {a, c} - Expected Edges: (b, a), (b, c) – Vertex c: - Adjacency List: {a, b, d, e} - Expected Edges: (c, a), (c, b), (c, d), (c, e) – Vertex d: - Adjacency List: {c, e} - Expected Edges: (d, c), (d, e) – Vertex e: - Adjacency List: {c, d} - Expected Edges: (e, c), (e, d) • Since every vertex’s adjacency list correctly represents the edges in Figure 1, the two graphs are equal. is this answer correct?

For parts (a) and (b), indicate if each of the two graphs are equal. Justify your answer. (Includes adjacency list and graph comparison)

Solution

Yes, the answer provided is correct.

The solution involves comparing the adjacency list representation of the graph to the graphical representation to ensure they describe the same structure. The steps are clearly outlined:

  1. The vertex set is the same for both representations: V={a,b,c,d,e}V = \{a, b, c, d, e\}.
  2. For each vertex in the graph, the adjacency list corresponds exactly to the edges shown in the graphical diagram.
    • For vertex a, the adjacency list shows {b, c}, matching the edges (a, b) and (a, c).
    • For vertex b, the adjacency list shows {a, c}, matching the edges (b, a) and (b, c).
    • For vertex c, the adjacency list shows {a, b, d, e}, matching the edges (c, a), (c, b), (c, d), and (c, e).
    • For vertex d, the adjacency list shows {c, e}, matching the edges (d, c) and (d, e).
    • For vertex e, the adjacency list shows {c, d}, matching the edges (e, c) and (e, d).

Since each vertex's adjacency list corresponds accurately to the edges in the graphical representation, the two graphs are indeed equal.

Would you like further explanation or clarification on any specific part of this?

Here are some related questions:

  1. What is the definition of an adjacency list in graph theory?
  2. How would you represent an undirected graph using an adjacency matrix?
  3. Can a graph be represented by multiple adjacency lists? If so, how can we tell if they are the same graph?
  4. What are the differences between a directed and an undirected graph?
  5. What does it mean for two graphs to be isomorphic?

Tip: When comparing graphs, make sure to check both the structure of the graph and how each vertex is connected to others, as shown in both the adjacency list and the diagram.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Graph Theory
Undirected Graphs
Adjacency List
Graph Equality

Formulas

-

Theorems

Graph Isomorphism Theorem (for comparing two graphs for equality)

Suitable Grade Level

Grades 9-12