Contemporary Abstract Algebra
Contemporary Abstract Algebra
9th Edition
ISBN: 9781305657960
Author: Joseph Gallian
Publisher: Cengage Learning
Question
Book Icon
Chapter 1, Problem 1E
To determine

To Describe:Each symmetry in D3.

Expert Solution & Answer
Check Mark

Explanation of Solution

Given: An equilateral triangle.

Calculation:

Three rotations at 0, 120 and 240 gives the symmetric in an equilateral triangle and also flips over three different axes (vertex) at the midpoint of the opposite side gives the symmetric in an equilateral triangle. So total there are six symmetries in equilateral triangle.

The three rotations at 0, 120 and 240 which gives the symmetric are:

Contemporary Abstract Algebra, Chapter 1, Problem 1E , additional homework tip  1

The three symmetries obtain by flips over three different axes are -

Contemporary Abstract Algebra, Chapter 1, Problem 1E , additional homework tip  2

Thus, there are six symmetries in equilateral triangle.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!
Knowledge Booster
Background pattern image
Recommended textbooks for you
Text book image
Elementary Geometry for College Students
Geometry
ISBN:9781285195698
Author:Daniel C. Alexander, Geralyn M. Koeberlein
Publisher:Cengage Learning
Text book image
Elementary Geometry For College Students, 7e
Geometry
ISBN:9781337614085
Author:Alexander, Daniel C.; Koeberlein, Geralyn M.
Publisher:Cengage,
Text book image
Mathematics For Machine Technology
Advanced Math
ISBN:9781337798310
Author:Peterson, John.
Publisher:Cengage Learning,
Text book image
Linear Algebra: A Modern Introduction
Algebra
ISBN:9781285463247
Author:David Poole
Publisher:Cengage Learning
Text book image
Holt Mcdougal Larson Pre-algebra: Student Edition...
Algebra
ISBN:9780547587776
Author:HOLT MCDOUGAL
Publisher:HOLT MCDOUGAL
Text book image
Algebra & Trigonometry with Analytic Geometry
Algebra
ISBN:9781133382119
Author:Swokowski
Publisher:Cengage