Show that the multiplicative group Z is isomorphic to the group Z2 X Z2 8,

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
100%
**Title: Isomorphism of Multiplicative and Cartesian Groups**

**Objective:**
Show that the multiplicative group \(\mathbb{Z}_8^\times\) is isomorphic to the group \(\mathbb{Z}_2 \times \mathbb{Z}_2\).

**Problem Statement:**
The task is to demonstrate that the multiplicative group of units modulo 8, denoted \(\mathbb{Z}_8^\times\), is structurally identical to the direct product of the cyclic group of order 2, denoted \(\mathbb{Z}_2\), with itself.

This means we need to find a bijective homomorphism:
\[ f: \mathbb{Z}_8^\times \to \mathbb{Z}_2 \times \mathbb{Z}_2 \]
which is a function that preserves the group operation, ensuring that the structure of \(\mathbb{Z}_8^\times\) matches that of \(\mathbb{Z}_2 \times \mathbb{Z}_2\).

To begin, let's examine the elements of each group.

### Elements:
- \(\mathbb{Z}_8^\times\): The group of units modulo 8 consists of those integers less than 8 that are coprime to 8. These elements are {1, 3, 5, 7}.
- \(\mathbb{Z}_2\): The cyclic group of order 2 consists of the elements {0, 1}.
- \(\mathbb{Z}_2 \times \mathbb{Z}_2\): This direct product consists of the ordered pairs {(0,0), (0,1), (1,0), (1,1)}.

### Verification:
Now, we will establish the isomorphism by verifying the group structure.

1. **Group Operation Preservation:**
   - For \(\mathbb{Z}_8^\times\), the operation is multiplication modulo 8.
   - For \(\mathbb{Z}_2 \times \mathbb{Z}_2\), the operation is component-wise addition modulo 2.

2. **Bijection and Homomorphism:**
   - Define a mapping \( f \) from \(\mathbb{Z}_8^\times\) to \(\mathbb{Z}_2 \times \mathbb{Z}_2\).
Transcribed Image Text:**Title: Isomorphism of Multiplicative and Cartesian Groups** **Objective:** Show that the multiplicative group \(\mathbb{Z}_8^\times\) is isomorphic to the group \(\mathbb{Z}_2 \times \mathbb{Z}_2\). **Problem Statement:** The task is to demonstrate that the multiplicative group of units modulo 8, denoted \(\mathbb{Z}_8^\times\), is structurally identical to the direct product of the cyclic group of order 2, denoted \(\mathbb{Z}_2\), with itself. This means we need to find a bijective homomorphism: \[ f: \mathbb{Z}_8^\times \to \mathbb{Z}_2 \times \mathbb{Z}_2 \] which is a function that preserves the group operation, ensuring that the structure of \(\mathbb{Z}_8^\times\) matches that of \(\mathbb{Z}_2 \times \mathbb{Z}_2\). To begin, let's examine the elements of each group. ### Elements: - \(\mathbb{Z}_8^\times\): The group of units modulo 8 consists of those integers less than 8 that are coprime to 8. These elements are {1, 3, 5, 7}. - \(\mathbb{Z}_2\): The cyclic group of order 2 consists of the elements {0, 1}. - \(\mathbb{Z}_2 \times \mathbb{Z}_2\): This direct product consists of the ordered pairs {(0,0), (0,1), (1,0), (1,1)}. ### Verification: Now, we will establish the isomorphism by verifying the group structure. 1. **Group Operation Preservation:** - For \(\mathbb{Z}_8^\times\), the operation is multiplication modulo 8. - For \(\mathbb{Z}_2 \times \mathbb{Z}_2\), the operation is component-wise addition modulo 2. 2. **Bijection and Homomorphism:** - Define a mapping \( f \) from \(\mathbb{Z}_8^\times\) to \(\mathbb{Z}_2 \times \mathbb{Z}_2\).
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 2 steps

Blurred answer
Knowledge Booster
Groups
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.
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,