Let G be an abelian group and n be a fixed positive integer. LetH={gn|g∈G}andK={x∈G|xn =e},show tha tH<G and K<G.
Extra challenge: Show that the statement may not be true when G is not abelian
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If you have any doubt or need more clarification at any step please comment.
Let G be an abelian group and n be a fixed positive integer. LetH={gn|g∈G}andK={x∈G|xn =e},show tha...
Abstract algebra A. Assume G is an abelian group. Let n > 0 be an integer. Prove that f(x) = ?" is a homomorphism from Got G. B. Assume G is an abelian group. Prove that f(x) = 2-1 is a homomorphism from Got G. C. For the (non-abelian) group S3, is f(x) = --! a homomorphism? Why?
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...
(7 marks) Let n be a positive integer and let G be a group such that there is a surjective homomorphism from G onto the symmetric group Sn. Show that G has a normal subgroup of index 2.
Let G be any group and n>1 a fixed integer such that (xy)n=xnyn for all x,y in G . H={ an , a belong to G } show that H is a normal subgroup .
Ok = (6) Let n be a positive integer. For every integer k, define the 2 x 2 matrix cos(27k/n) - sin(2nk/n) sin(2tk/n) cos(27 k/n) (a) Prove that go = I, that ok + oe for 0 < k < l< n - 1, and that Ok = Okun for all integers k. (b) Let o = 01. Prove that ok ok for all integers k. (c) Prove that {1,0,0%,...,ON-1} is a finite abelian group of order n.
proof please 51. Let H and K be subgroups of an abelian group G of orders n and m respectively. Show that if H K = {e}, then HK = {hkh e H and ke K} is a subgroup of G of order nm.
let G be a finite group, prove that for every a in G there exists a positive integer n such that an=e, the identity.
(3) (7 points) Let G be a finite abelian group of order n. Let k be relatively prime to n. Prove the map : G G given by pla) = ak is an automor- phism of G
(a) Show that if H and K are subgroups of an abelian group G, then HK = {hk|he H, k E K} is a subgroup of G (b) Show that if H and K are normal subgroups of a group G, then H N K is a normal subgroup of G
2. Let G {g, g. . . , gn-le} be a cyclic group of order n, H a group, and h є H. Define a function φ : G → H by φ(gi-hi for all 0 < i n-1. Show that φ is a group homomor- phism if and only if o(h) divides o(g). Warning: mind your modular arithmetic! [10]