文档介绍：离散数学****题参考答案
集合
,描述法写出下列集合
偶数集合
(２)36的正因子集合
(３)自然数中3的倍数
(４)大于１的正奇数
E={¼,-6,-4,-2,0,2,4,6,¼}
={2 i | i I }
(2) D= { 1, 2, 3, 4, 6, } = {x>o | x|36 }
(3) N3= { 3, 6, 9, ```} = { 3n | nN }
(4) Ad= {3, 5, 7, 9, ```} = { 2n+1 | nN }

(１)φφ ×
(２)φ｛φ｝√
(３)φφ√
(４)φ｛φ｝√
(５)φ｛ａ｝×
(６)φ｛ａ｝√
(７)｛ａ,ｂ｝｛ａ,ｂ,ｃ,｛ａ,ｂ,ｃ｝｝×
(８)｛ａ,ｂ｝｛ａ,ｂ,ｃ,｛ａ,ｂ,ｃ｝｝√
(９)｛ａ,ｂ｝｛ａ,ｂ,｛｛ａ,ｂ｝｝｝×
(１０)｛ａ,ｂ｝｛ａ,ｂ,｛｛ａ,ｂ｝｝｝√

(１)｛｛ａ｝｝
{φ, {{ a }}}
( 2 ) φ
{φ}
(３)｛φ,｛φ｝｝
{φ, {φ}, {{φ}}, {φ,{φ}} }
(４)｛φ,ａ,｛ａ,ｂ｝｝
{φ, {a}, {{a,b }}, {φ}, {φ, a }, {φ, {a,b }},
{a, {a b }}, {φ,a,{ a, b }} }
(５)Ｐ(Ｐ(φ))
{φ, {φ}, {{φ}}, {φ,{φ}} }
,Ｂ,Ｃ,确定下列结论的正确与否
(１)若ＡＢ,且ＢＣ,则ＡＣ√
(２)若ＡＢ,且ＢＣ,则ＡＣ×
(３)若ＡＢ,且ＢＣ,则ＡＣ×
(４)若ＡＢ,且ＢＣ,则ＡＣ ×
,Ｂ,Ｃ,证明

,集合Ａ,Ｂ,Ｃ满足下列等式

＝｛ａ,ｂ,｛ａ,ｂ｝,｝,求下列各式
(１)φ∩｛φ｝=φ
(２)｛φ｝∩｛φ｝={φ} 
(３)｛φ,｛φ｝｝－φ={φ,{φ}}
(４)｛φ,｛φ｝｝－｛φ｝= {{φ}}
(５)｛φ,｛φ｝｝－｛｛φ｝｝={φ}
(６)Ａ－｛ａ,ｂ｝={{a,b}, φ}
(７)Ａ－φ = A
(８)Ａ－｛φ｝={a,b,{a,b}}
(９)φ－Ａ=φ
(１０)｛φ｝－Ａ=φ
,一定有Ｂ＝Ｃ不？
否,例:A={1,2,3},B={4},C={3,4},
。
(２)
否,例:A={1,2,3},B={2,3},C={2,3,4