6.若集合,,则集合等于( )
{|23}A x x =-≤≤{|14}B x x x =<->或A B A . B .C . D .
{}|34x x x ≤>或{}|13x x -<≤{}|34x x ≤<(2008北京文)
{}|21x x -≤-<7.若为全体正实数的集合,则下列结论正确的是( )
A {}2,1,1,2
B =--A .B . }
{2,1A B =--I ()(,0)R C A B =-∞ C .D .(2008安徽卷文1)
(0,)A B =+∞ }{()2,1R C A B =--I 8.设集合,,则{}22,A x x x R =-≤∈{}2|,12B y y x x ==--≤≤()R C A B 等于( )
A .
B .
C .
D .R {}
,0x x R x ∈≠{}0∅
(2006安徽理1)9.定义集合运算,则集合*{,,},{1,2},{0,2}A B Z Z xy x A y B A B =|=∈∈==设*A B 的所有元素之和为( )。
A . 0 B.2 C. 3 D. 6(2008江西)
10.已知集合M ={x |x 2<4},N ={x |x 2-2x -3<0},则集合M ∩N 等于( )
A.{x |x <-2}
B.{x |x >3}
C.{x |-1<x <2}
D.{x |2<x <3}(2004全国Ⅱ1)
解析:M ={x |x 2<4}={x |-2<x <2},N ={x |x 2-2x -3<0}={x |-1<x <3},结合数轴,
∴M ∩N ={x |-1<x <2}.
11.已知集合A={x ∈R|3x+2>0} B={x ∈R|(x+1)(x-3)>0} 则A ∩B=
A (-∞,-1)
B (-1,-
23) C (-23
,3)D (3,+∞) 12.已知全集,集合,则为
{}0,1,2,3,4U ={}{}1,2,3,2,4A B ==U C A B (A ) (B ) (C ) (D ){}1,2,4{}2,3,4{}0,2,4{}
0,2,3,413.集合,,则( )
{|lg 0}M x x =>2
{|4}N x x =≤M N = A. B. C. D. (1,2)[1,2)(1,2][1,2]14.设全集U =R ,,,那么下列关系中正确的是--------}2|{>=x x M }21|
{<=x
x N ----------( ) A . B . C . D .M N =M N ≠⊂N M ≠⊂φ
=N M 15.若集合121log 2A x x ⎧⎫⎪
⎪=≥⎨⎬⎪⎪⎩⎭
,则A =R ðA
、(,0]⎫-∞+∞⎪⎪⎭ B
、⎫+∞⎪⎪⎭
C
、(,0])-∞+∞ D
、)
+∞16.已知集合A={x },B={x },则A B=( )
1x >2x 1-<< (A ) {x } (B ){x } (C ){x } (D ){x 2x 1-<<1-x >1x 1-<<2x 1<<}(2011辽宁文1)
【精讲精析】选D ,解不等式组,得.所以A B=..⎩
⎨⎧<<->211x x 21<17.已知全集U=R ,集合,则等于
2
{|20}A x x x =->U A ðA . { x ∣0x 2} B { x ∣0≤≤C . { x ∣x<0或x>2} D { x ∣x 0或x 2}(2009福建卷理)≤≤18.设集合={| },={|}.则=
S x 5x x x x C. {| -5 <<3} D. {| -7<<5 }. (2009四川卷文
x x x x 19.已知全集中有m 个元素,中有n 个元素.若非空,则U =A B ()()U U A B ððA B I 的元素个数为
A B I A . B . C . D . (2009江西卷理)
mn m n +n m -m n -20.集合,,若,则的值为( ){}0,2,A a ={}2
1,B a ={}0,1,2,4,16A B = a A.0 B.1 C.2 D.4(2009山东卷理)【解析】:∵,,∴∴,故选D.
{}0,2,A a ={}21,B a ={}0,1,2,4,16A B = 2164
a a ⎧=⎨=⎩4a =21.设,,,则( )
U =R {|0}A x x =>{|1}B x x =>U A B = ðA . B . C . D . (2009浙江理)
{|01}x x ≤<{|01}x x <≤{|0}x x <{|1}x x >22.下列集合中,表示同一集合的是( D )
A. M={(3,2)},N={(2,3)}
B. M={3,2},N={(3,2)}
C. M={(x,y )∣x+y =1},N={y ∣x+y =1}
D. M={3,2},N={2,3}
23.设全集为I ,非空集合A ,B 满足A ⊂B ,则下列集合中为空集的是-----------------------------( )
A. B.A ∩B C. D.I A B ðI I A B ððI A B
ð24.集合满足,则————————( )
,,M N P N P N N N M =⋂=⋃,(A )(B )(C )(D )P M =P M ⊆P M ⊇P M ≠
⊂25.设M 、P 是两个非空集合,定义M 与P 的差集为,且M P {|x x M =∈-}x P ∉,则M -(M -P )( )