Let a ∈ G where G is a group. If X ⊆ G is a finite subset, write Xa = {xa | x ∈ X}. Show that X and Xa have the same number of elements.
Let G be a finite group of order n. Let φ : G → G be the function given by φ(x) = z'n where rn E N. If gcd(rn, n) = 1, show that φ s an injective map. Let G be a finite group of order n. Let φ : G → G be the function given by φ(x) = z'n where rn E N. If gcd(rn, n) = 1, show that φ s an injective map.
Let A be a subset of a finite group G with |A| > |G|/2. Prove that every element of G can be written as the product of two elements of A. Is this also always true when |A| = |G|/2?
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.
(10 pts) Let G be a finite group acting on a set X. Prove that the he number of orbits equals the quantity Σ9EG points of G. #4 X where for g G, X9 denotes the number of fixed (10 pts) Let G be a finite group acting on a set X. Prove that the he number of orbits equals the quantity Σ9EG points of G. #4 X where for g G, X9 denotes the number of fixed
Only 2 and 3 1.) Let G be a finite G be a finite group of order 125, 1. e. 161-125 with the identity elemente. Assume that contains an element a with a 25 t e, Show that is cyclic 2. Solve the system of congruence.. 5x = 17 (mod 12) x = 13 mod 19) 3.) Let G be an abelian. group Let it be a subgroup o G. Show that alt -Ha for any a EG
(9) Let G be a group, and let x E G have finite order n. Let k and l be integers. Prove that xk = xl if and only if n divides l_ k.
Let X be a finite set on which G acts, let ρ be the corresponding permutation representation [cf. 1.2, example (c)], and xx be the character of p. Let s E G; show that xx(s) is the number of elements of X fixed by s. Let X be a finite set on which G acts, let ρ be the corresponding permutation representation [cf. 1.2, example (c)], and xx be the character of p. Let s E G; show that xx(s)...
Let G be a group and g E G such that g) is finite. Let og be the automorphism of G given by 09(x) = grg- (a) Prove that $, divides g. (b) Find an element b from a group for which 1 < 0) < 1b.
Problem 1. Let G be a finite group and f : G → G a group automorphism ( isomorphism for G to G) of order 2 (i.e. f(f(x)) = x), and f has no nontrivial fixed points (i.e. f(x) = x if and only if x = 1). Prove that G is an abelian group of odd order.
Exercise 2. Let he a group anith nentral element e. We denote the gronp lau on G simply by (91,92)gig2. Let X be a set. An action ofG on X is a a map that satisfies the following tuo conditions: c. Let G be a finite group. For each E X, consider the map (aje- fer all elements r X (b) 9-(92-2) for all 91,92 G and all r E X Show that is surjective and that, for all y...