Contemporary Abstract Algebra
9th Edition
ISBN: 9781305657960
Author: Joseph Gallian
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Textbook Question
Chapter 3, Problem 15E
(1969 Putnam Competition) Prove that no group is the union of two proper subgroups. Does the statement remain true if “two” is replaced by “three”?
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionChapter 3 Solutions
Contemporary Abstract Algebra
Ch. 3 - For each group in the following list, find the...Ch. 3 - Let Q be the group of rational numbers under...Ch. 3 - Let Q and Q* be as in Exercise 2. Find the order...Ch. 3 - Prove that in any group, an element and its...Ch. 3 - Without actually computing the orders, explain why...Ch. 3 - In the group Z12 , find a,b,anda+b for each case....Ch. 3 - If a, b, and c are group elements and a=6,b=7 ,...Ch. 3 - What can you say about a subgroup of D3 that...Ch. 3 - What can you say about a subgroup of D4 that...Ch. 3 - How many subgroups of order 4 does D4 have?
Ch. 3 - Determine all elements of finite order in R*, the...Ch. 3 - Complete the statement “A group element x is its...Ch. 3 - For any group elements a and x, prove that xax1=a...Ch. 3 - Prove that if a is the only element of order 2 in...Ch. 3 - (1969 Putnam Competition) Prove that no group is...Ch. 3 - Let G be the group of symmetries of a circle and R...Ch. 3 - For each divisor k1 of n, let Uk(n)=xU(n)xmodk=1...Ch. 3 - Suppose that a is a group element and a6=e . What...Ch. 3 - If a is a group element and a has infinite order,...Ch. 3 - For any group elements a and b, prove that ab=ba .Ch. 3 - Show that if a is an element of a group G, then...Ch. 3 - Show that U(14)=3=5 . [Hence, U(14) is cyclic.] Is...Ch. 3 - Show that U(20)k for any k in U(20). [Hence, U(20)...Ch. 3 - Suppose n is an even positive integer and H is a...Ch. 3 - Let n be a positive even integer and let H be a...Ch. 3 - Prove that for every subgroup of Dn , either every...Ch. 3 - Let H be a subgroup of Dn of odd order. Prove that...Ch. 3 - Prove that a group with two elements of order 2...Ch. 3 - Prob. 29ECh. 3 - Prob. 30ECh. 3 - Prob. 31ECh. 3 - Suppose that H is a subgroup of Z under addition...Ch. 3 - Prove that the dihedral group of order 6 does not...Ch. 3 - If H and K are subgroups of G, show that HK is a...Ch. 3 - Let G be a group. Show that Z(G)=aGC(a) . [This...Ch. 3 - Let G be a group, and let aG . Prove that...Ch. 3 - For any group element a and any integer k, show...Ch. 3 - Let G be an Abelian group and H=xG||x is odd}....Ch. 3 - Prob. 39ECh. 3 - Prob. 40ECh. 3 - Let Sbe a subset of a group and let H be the...Ch. 3 - In the group Z, find a. 8,14 ; b. 8,13 ; c. 6,15 ;...Ch. 3 - Prove Theorem 3.6. Theorem 3.6 C(a) Is a Subgroup...Ch. 3 - If H is a subgroup of G, then by the centralizer...Ch. 3 - Must the centralizer of an element of a group be...Ch. 3 - Suppose a belongs to a group and a=5 . Prove that...Ch. 3 - Prob. 47ECh. 3 - In each case, find elements a and b from a group...Ch. 3 - Prove that a group of even order must have an odd...Ch. 3 - Consider the elements A=[0110]andB=[0111] from...Ch. 3 - Prob. 51ECh. 3 - Give an example of elements a and b from a group...Ch. 3 - Consider the element A=[1101] in SL(2,R) . What is...Ch. 3 - For any positive integer n and any angle , show...Ch. 3 - Prob. 55ECh. 3 - In the group R* find elements a and b such that...Ch. 3 - Prob. 57ECh. 3 - Prob. 58ECh. 3 - Prob. 59ECh. 3 - Compute the orders of the following groups. a....Ch. 3 - Let R* be the group of nonzero real numbers under...Ch. 3 - Compute U(4),U(10),andU(40) . Do these groups...Ch. 3 - Find a noncyclic subgroup of order 4 in U(40).Ch. 3 - Prove that a group of even order must have an...Ch. 3 - Let G={[abcd]|a,b,c,dZ} under addition. Let...Ch. 3 - Let H=AGL(2,R)detA is an integer power of 2}. Show...Ch. 3 - Let H be a subgroup of R under addition. Let...Ch. 3 - Let G be a group of functions from R to R*, where...Ch. 3 - Let G=GL(2,R) and...Ch. 3 - Let H=a+bia,bR,ab0 . Prove or disprove that H is...Ch. 3 - Let H=a+bia,bR,a2+b2=1 . Prove or disprove that H...Ch. 3 - Let G be a finite Abelian group and let a and b...Ch. 3 - Prob. 73ECh. 3 - If H and K are nontrivial subgroups of the...Ch. 3 - Prob. 75ECh. 3 - Prove that a group of order n greater than 2...Ch. 3 - Let a belong to a group and a=m. If n is...Ch. 3 - Let G be a finite group with more than one...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, algebra and related others by exploring similar questions and additional content below.Similar questions
- Let H and K be subgroups of a group G and K a subgroup of H. If the order of G is 24 and the order of K is 3, what are all the possible orders of H?arrow_forwardTrue or False Label each of the following statements as either true or false. In a Cayley table for a group, each element appears exactly once in each row.arrow_forwardFind two groups of order 6 that are not isomorphic.arrow_forward
- Prove that Ca=Ca1, where Ca is the centralizer of a in the group G.arrow_forwardExercises 19. Find cyclic subgroups of that have three different orders.arrow_forward15. Assume that can be written as the direct sum , where is a cyclic group of order . Prove that has elements of order but no elements of order greater than Find the number of distinct elements of that have order .arrow_forward
- Label each of the following statements as either true or false. Two groups can be isomorphic even though their group operations are different.arrow_forwardExercises 10. Find an isomorphism from the multiplicative group to the group with multiplication table in Figure . This group is known as the Klein four group. Figure Sec. 16. a. Prove that each of the following sets is a subgroup of , the general linear group of order over . Sec. 3. Let be the Klein four group with its multiplication table given in Figure . Figure Sec. 17. Show that a group of order either is cyclic or is isomorphic to the Klein four group . Sec. 16. Repeat Exercise with the quaternion group , the Klein four group , and defined byarrow_forwardFind all subgroups of the octic group D4.arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Elements Of Modern AlgebraAlgebraISBN:9781285463230Author:Gilbert, Linda, JimmiePublisher:Cengage Learning,
Elements Of Modern Algebra
Algebra
ISBN:9781285463230
Author:Gilbert, Linda, Jimmie
Publisher:Cengage Learning,
Orthogonality in Inner Product Spaces; Author: Study Force;https://www.youtube.com/watch?v=RzIx_rRo9m0;License: Standard YouTube License, CC-BY
Abstract Algebra: The definition of a Group; Author: Socratica;https://www.youtube.com/watch?v=QudbrUcVPxk;License: Standard Youtube License