16. Let Z(G), the center of G, be the set of elements of G that commute...
22 Must the center of a group be Abelian? 23. Let G be an Abelian group with identity e and let n be some integer Prove that the set of all élements of G that satisfy the equation* - e is a subgroup of G. Give an example of a group G in which the set of all elements of G that satisfy the equation :2 -e does not form a subgroup of G. (This exercise is referred to in...
#21. Let G be the set of all real 2 x 2 matrices where ad + 0, Prove that under matrix multiplication. Let N = (a) N is a normal subgroup of G. (b) G/N is abelian.
[8 pts) Let G be a group and the center of G is defined as Z(G) = {x € G | xg = gx for all g € G}. In Homework 3, we have showed that the center Z(G) is a subgroup of G. Let H be a subgroup of G. Prove that the set HZ(G) = {hz|he H,2 E Z(G)} is a subgroup of G.
1. Let G - Z. Let H - {0,3,5,9) be a subgroup of (you do not need to prove this is a subgroup of G). Prove that G/l is a valid quotient group. Explain what the elements of G/H are and what the group operation is. 2. Let G be a group and H a normal subgroup in G. I E H for all IEG, then prove that G/H is abelian
2. The center of a group G is the set (a) Prove that Z(G) is a subgroup of G, and that it is normal in G (b) Compute the center of the following groups: GG, Di D, Qs, At, Sa, and Dax Qs 2. The center of a group G is the set (a) Prove that Z(G) is a subgroup of G, and that it is normal in G (b) Compute the center of the following groups: GG, Di D,...
(2) For an integer n, let Z/nZ denote the set of equivalence classes [k) tez: k -é is divisible by n (a) Prove that the set Z/nZ has n elements. (b) Find a minimal set of representatives for these n elements. (c) Prove that the operation gives a well-defined addition on Z/nZ Hint: The operution should not depend on the choice of coset representatives Verify that this gives Z/n2 the structure of an ahelian group. Be sure to verify all...
Let M be the set of 2 x 2 matrices of the form (82) where a, d ER-{0}. Consider the usual matrix multiplication, i.e: ae + bg af +bh ce + dg cf + dh (2)) = (ce ) (a) Show that (M,-) is an abelian group. (b) Compute the cyclic subgroup generated by M = What is the order of M? (6 -4) € M.
Question 4 Exercise 1. Let G be a group such that |G| is even. Show that there exists an EG,17e with x = e. Exercise 2. Let G be a group and H a subgroup of G. Define a set K by K = {z € G war- € H for all a € H}. Show that (i) K <G (ii) H <K Exercise 3. Let S be the set R\ {0,1}. Define functions from S to S by e(z)...
4. Let M be the set of 2 x 2 matrices of the form (62) where a, d E R - {0}. Consider the usual matrix multiplication ·, i.e: ae + bg af + bh ce + dg cf + dh (a) Show that (M,·) is an abelian group. 1 (b) Compute the cyclic subgroup generated by M = What is the order of M? 66 -4) (1) EM EM.
Exercise 3 1- What are the symmetry elements of the NH molecule whose four atoms occupy the corners of a regular tetrahedron. Molecular geometry of NH 2- Make the stereographic projection of symmetry elements and equivalent positions generated by its operations 3- Give the elements of the corresponding point group. Specify its order and its international notation. 4- Establish the multiplication table of this group specify its rank. 5- Is the group Abelian? Describe all subgroups of this group. Afif...