Show that if H is a subgroup of G and a^-1b is an element of H, then aH is a subset of bH.
If H is a subgroup of G then what is the set G/H? Under what conditions does the prescription aH * bH = abH give a well defined group structure on G/H?
3. a. Let H be a subgroup of a commutative group G. If every element h ∈ H is a square in H (i.e., h = k 2 for some k ∈ H), and every element of G/H is a square in G/H, then every element of G is a square in G. b. Let G be a group and H a subgroup with [G : H] = 2. If g ∈ G has odd order (i.e., ord(g) is odd),...
Let G be a finite group and let H be a subgroup of G. Show using double cosets that there is a subset T of G which is simultaneously a left transversal for H and a right transversal for H.
Let H be a subgroup of G. Define the normalizer of H in G to be the subset NG(H) {g € G |gHg= H}. (i) Prove that NG(H) is a subgroup of G that contains H (ii) Prove that Ha NG(H) (iii) Prove that if H < K < G, and H K, then KC NG(H)
2. problem 3. Let H be a normal subgroup of a group G and let K be any subgroup of G. Prove that the subset HK of G defined by is a subgroup of G Let G S, H ), (12) (34), (13) (24), (1 4) (23)J, and K ((13)). We know that H is a normal subgroup of S, so HK is a subgroup of S4 by Problem 2. (a) Calculate HK (b) To which familiar group is HK...
11. Prove that a nonempty subset H of a group G is a subgroup of G if and only if whenever a, b E H, then ab-1 e H
abstract algebra show your work 3. Let H be a subgroup of G with |G|/\H = 2. Prove that H is normal in G. Hint: Let G. If Hthen explain why xH is the set of all elements in G not in H. Is the same true for H.C? Remark: The above problem shows that A, is a normal subgroup of the symmetric group S, since S/A, 1 = 2. It also shows that the subgroup Rot of all rotations...
Suppose H is a subset of G is a normal subgroup of index k. Prove that for any a in G, a to the power of k in H. Does this hold without the normality assumption?
Exercise 4. Consider the permutation group S7. a. Show that the subgroup generated by the element (1,2,3,4,5,6) is a cyclic group of order 6. b. Show that the subgroup generated by the element (1,3, 4, 5, 6, 7) is a cyclic group of order 6. c. Show that the subgroup generated by the element (1,2,3) is a cyclic group of order 3. d. Show that the subgroup generated by the element (6, 7) is a cyclic group of order 2....
Let G be a finite group, and let H be a subgroup of order n. Suppose that H is the only subgroup of order n. Show that H is normal in G. [consider the subgroup of G] aha а