caun cu suugroup. (2) Let (a b) be a transposition in Sn, and let a E...
Problem 21.13. Fory E Z+, let Aj (L. . . have B CU-1Aj. Is B necessarily finite? Prove it or give a counterexample. ,j). Suppose that for some n E Z+, we
Problem 21.13. Fory E Z+, let Aj (L. . . have B CU-1Aj. Is B necessarily finite? Prove it or give a counterexample. ,j). Suppose that for some n E Z+, we
2. Let X1, X2, X3 ..., X, be iid b(1, p) random variables. Let Sn = 27-1Xthen prove that Sn-E(Sn) N(0,1) as n +00. (Sn)
Let U be a set, and let A CU. Recall the indicator function XA: U + Z, defined by XA(x) = ſi, rEA 0, A. Now, let A, B CU and consider the symmetric difference of A and B defined by A AB= (A - B)U(B - A). (a) Show that AAB CU, and compute Ø A A. (b) Prove that Ve EU, XAAB(C) = XA(2) + XB(2), where addition is taken modulo 2 (so that 1+1 = 0).
2. Let U be a set, and let A CU. Recall the indicator function XA: U → Z2 defined by XA() : S 1, XEA 10, x¢ A. Now, let A, B CU and consider the symmetric difference of A and B defined by A A B = (A – B) U (B – A). (a) Show that A AB CU, and compute Ø A A. (b) Prove that Vx € U, XAAB(x) = x1(x) + XB(x), where addition is...
OTO (7) (a) Let T = (a1, ..., ak) be a k-cycle in Sn, and let o E Sn. Prove that is the k-cycle (o(a), o(az),..., 0(ak)) (b) Let o,t e Sn. Prove that if t is a product of r pairwise disjoint cycles of lengths k1,..., kr, respectively, where kit..., +kr = n, then oto-1 is also a product of r pairwise disjoint cycles of lengths k1,..., kr. (c) Let T1 and T2 be permutations in Sn. Prove that...
A. Let (X, d) be a metric space so that for every E X and every r>0 the closed ball N,(z) = {ye X : d(y, z) < r} is com pact. Let be a homeomorphism. (1) Prove that f"-+m-fn。fm for all n, m E Z. (2) Let z E X and suppose that F, {fn (z) : n E 2) is a closed subset of X Prove that F is a discrete subset of X (A subset Y C...
How to do (d) and (e)? Thanks.
11. Let X, X1, X2, ... be independent and identically distributed random variables taking values 0, 1, 2 with px(0) = 1, px(1) = 3 and px(2) = 1. Define Sn X1 Xn, n > 1. (a) Compute the probability generating function of X (b) Find the probability generating function of Sp. 2) from the probability generating function (c) Find P(Sn (d) Derive the moment generating function of S from its probability generating...
9·Let m, n E Z+ with (m, n) 1. Let f : Zmn-t Zrn x Zn by, for all a є z /([a]mn) = ([a]rn , [a]n). (a) Prove that f is well-defined. (b) Let m- 4 and n - 7. Find a Z such that f ([al28) (34,(517). (c) Prove that f is a bijection.2 (HINT: To prove that f is onto, given (bm, [cm) E Zm x Zn, consider z - cmr + bns, where 1 mr +ns.)
Question 1# (a) Let G be a connected graph and C a non-trivial circuit in G. Prove directly that if an edge e fa, b is removed from C then the subgraph S C G that remains is still connected. "Directly' means using only the definitions of the concepts involved, in this case connected' and 'circuit'. Hint: If z and y are vertices of G connected by path that includes e, is there an alternative path connecting x to y...
3. Let a, b, c E Z such that ca and (a,b) = 1. Show that (c, b) = 1. 4. Suppose a, b, c, d, e E Z such that e (a - b) and e| (c,d). Show that e (ad — bc). 5. Fix a, b E Z. Consider the statements P: (a, b) = 1, and Q: there exists x, y E Z so that ax + by = 1. Bézout’s lemma states that: if P, then...