Lecture 15 denote the group of integers under addition, Exercise 15.1: Let G denote the group...
(*) Let G be a group. Let G, G denote the smallest subgroup of G containing S = {xyr-ly-1: 2, YEG}. (The subgroup (G,G] is called the commutator subgroup of G.) (a) Show that u-zyr-?-?u= (u-cu)(u-yu)(u--xu)-1(u-yu)-1 for all 2, 4, U E G. Deduce that (G,G| 4G. (b) Show that the quotient group G/[G,G] is abelian. (c) If N 4G and G/N is abelian, show that (G,G] C N. (In other words, G/(G,G) is the largest abelian quotient of G.)...
(18) Let f and g be functions from R to R that have derivatives of al orders. Let h(k) denote the kth derivative of any function. Prove using the product rule for derivatives, the fact that and induction that k +1 k=0 (19) The Fibonacci numbers are defined recursively by Fn+2 = Fn+1 Prove that the number of subsets of { 1, 2, 3, . . . , n} containing no two successive integers is E, (20) Prove that 7n...
Always give rigorous arguments I. (A) Let G be a group under * and let g E G with o(g) = n (finite) (i) Show that g can never go back to any previous positive power of g* (1k< n) when taking up to the nth power (cf. g), e., that there are no integers k and m such that 1< k<m<n and such that g*-gm (ii) How many elements of the set (e, g,g2.... .g"-) are actually distinct? (iii)...
Exercise 2. Let φ denote the Euler totient function. (i) Prove that for all positive integers m and n, if m,n are relatively prime (coprime), then φ(mn-o(m)o(n) (ii) Is the converse true? Prove or provide a counter-example.
ei0 : 0 E R} be the group of all complex numbers on the unit circle under multiplication. Let ø : R -> U 1. (30) Let R be the group of real numbers under addition, and let U be the map given by e2Tir (r) (i) Prove that d is a homomorphism of groups (ii) Find the kernel of ø. (Don't just write down the definition. You need to describe explicit subset of R.) an real number r for...
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)...
Only need answer from (IV) to (VI)
Only need answer from (IV) to (VI)
Math 3140 page 1 of 7 1. (30) Let R be the group of real numbers under addition, and let U = {e® : 0 E R} be the group of all complex numbers on the unit circle under multiplication. Let o: R U be the map given by = e is a homomorphism of groups. (i) Prove that (i) Find the kernel of . (Don't...
Let G = {3m6n | m, n e Z}, which is a group under the operation of multiplication. (For example, 3263.3162 = 3365.) Prove that G = ZOZ, where both of these Z's are groups under addition.
(1) Show that the non-zero residue classes of the integers (mod n) form a group under multiplication if n is prime. motional numbers, let addition and
Let G be a group of order 231 = 3 · 7 · 11. Let H, K and N
denote sylow 3,7 and 11-subgroups of G, respectively.
a) Prove that K, N are both proper subsets of G.
b) Prove that G = HKN.
c) Prove that N ≤ Z(G). (you may find below problem useful).
a): <|/ is a normal subgroup, i.e. K,N are normal subgroups
of G
(below problem): Let G be a group, with H ≤ G...