精華區beta NTU-Exam 關於我們 聯絡資訊
課程名稱︰代數導論一 課程性質︰必修 課程教師︰莊武諺 開課學院:理學院 開課系所︰數學系 考試日期(年月日)︰2013/11/21 考試時限(分鐘):30分鐘 試題 : 代數導論第四次小考 INTRODUCTION TO ALGEBRA I - QUIZ IV NOV 21 2013 (1) (20 points) Let τ and σ be two elements of the permutation group S_n. Suppose the cycle decomposition of σ is given by (a_1 a_2 … a_k1)(b_1 b_2 … b_k2)…. Show that τσ(τ^-1) has the cycle decomposition (τ(a_1) τ(a_2) … τ(a_k1))(τ(b_1) τ(b_2) … τ(b_k2))…. (2) (15 points) Let G be a group and H be a normal subgroup of G. Show that for every conjugacy class Κ of G, we have either Κ ⊂ H or K ∩ H = ψ. (ψ denotes empty set) (3) (15 points) There are 7 conjugacy classes in S_5. Please write down a representative for each conjugacy class and compute the number of elements in each class. -- ※ 發信站: 批踢踢實業坊(ptt.cc), 來自: 118.166.208.40 ※ 文章網址: https://www.ptt.cc/bbs/NTU-Exam/M.1423621122.A.DA6.html ※ 編輯: Malzahar (118.166.208.40), 02/11/2015 10:18:54