GROUP holds four properties simultaneously: i) Closure, ii) Associative, iii) Identity element; and iv) Inverse element. Give an illustrative example for each statement to prove whether GROUP or NOT A GROUP. 1. The set of integers Z, the set of rational numbers Q, and the set of real numbers R are all groups under ordinary addition. 2. The set of integers under ordinary multiplication is not a group. 3. The set of positive irrational numbers together with 1 under multiplication satisfies the three properties given in the definition of a group but is not a group. Why? 4. The set R* of nonzero real numbers is a group under ordinary multiplication. 5. A rectangular array of the form [] is called a 2 x 2 matrix. The set of all 2 x 2 matrices with real entries is a group under component wise addition.

Algebra: Structure And Method, Book 1
(REV)00th Edition
ISBN:9780395977224
Author:Richard G. Brown, Mary P. Dolciani, Robert H. Sorgenfrey, William L. Cole
Publisher:Richard G. Brown, Mary P. Dolciani, Robert H. Sorgenfrey, William L. Cole
Chapter2: Working With Real Numbers
Section2.1: Basic Assumptions
Problem 40WE
icon
Related questions
Question
GROUP holds four properties simultaneously:
i)
Closure,
ii)
Associative,
Identity element; and
iv) Inverse element.
Give an illustrative example for each statement to prove whether GROUP or NOT A GROUP.
1. The set of integers Z, the set of rational numbers Q, and the set of real numbers Rare
all groups under ordinary addition.
2. The set of integers under ordinary multiplication is not a group.
3. The set of positive irrational numbers together with 1 under multiplication satisfies the
three properties given in the definition of a group but is not a group. Why?
4. The set R* of nonzero real numbers is a group under ordinary multiplication.
5. A rectangular array of the form [] is called a 2 x 2 matrix. The set of all 2 x 2
matrices with real entries is a group under component wise addition.
Transcribed Image Text:GROUP holds four properties simultaneously: i) Closure, ii) Associative, Identity element; and iv) Inverse element. Give an illustrative example for each statement to prove whether GROUP or NOT A GROUP. 1. The set of integers Z, the set of rational numbers Q, and the set of real numbers Rare all groups under ordinary addition. 2. The set of integers under ordinary multiplication is not a group. 3. The set of positive irrational numbers together with 1 under multiplication satisfies the three properties given in the definition of a group but is not a group. Why? 4. The set R* of nonzero real numbers is a group under ordinary multiplication. 5. A rectangular array of the form [] is called a 2 x 2 matrix. The set of all 2 x 2 matrices with real entries is a group under component wise addition.
Expert Solution
steps

Step by step

Solved in 7 steps

Blurred answer