精華區beta NTU-Exam 關於我們 聯絡資訊
課程名稱︰密碼學 課程性質︰選修 課程教師︰陳君明 開課學院:理學院 開課系所︰數學系 考試日期(年月日)︰2012/3/21 考試時限(分鐘):40 min 是否需發放獎勵金:是 (如未明確表示,則不予發放) 試題 : s = ____ = 12 - "the last digit of your ID", 3 <= s <= 12 1) Consider the group G = (Z17*, ×mod 17) a) s^-1(the multiplicative inverse of s) is ____ b) o(s) (the order of s) = ____ c) The index [G, <s>] = ____ d) Explain why G is a cyclic group. 2) Consider the homomorphism f:(Z16, + mod 16) →(Z17*, ×mod 17), defined by f(1) = s. a) f(0) = ____ b) f(2) = ____ c) Is f an isomorphism? Explain. 3) |GL2(Z17)| = ____, |SL2(Z17)| = ____ 4) Consider the sumtric group S4 a) |S4| = ____ b) ╭1 2 3 4╮ │ │= ____ ╰3 1 4 2╯ c) ╭1 2 3 4╮ ╭1 2 3 4╮ │ │.│ │= ____ ╰3 1 4 2╯ ╰2 1 4 3╯ 5) Which rins are integral domains? ____ a) Z b) Z6 c) Z7 d) Z[x]/<x^2+1> e)Z[x]/<x^2-1> 6) Suppose H is a subgroup of G, prove that two left cosets g1H = g2H if and only if (g1^-1)g2 屬於 H -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 118.160.163.172
rod24574575 :你有把題目照下來喔... 04/03 07:35
tsf73 :是啊 我有 04/03 11:54
yuricon :樓樓上rod推 04/03 21:55
s864372002 :樓下jmc: 04/08 13:15