一、填空题
1设集合A,B，其中A＝{1,2,3},B={1,2},则A-B＝__{3}__________________;
(A-(B＝___________________{3},{1,3},{2,3},{123}______.
2.设有限集合A,|A|=n,则|(A×A|=_____2^(n^2_____________________.
3.设集合A={a,b},B={1,2},则从A到B的所有映射是_______________________________________,其中双射的是__________________________.
4.已知命题公式G＝(PQ∧R，则G的主析取范式是_________________________________________________________________________________________.
5.设G是完全二叉树，G有7个点，其中4个叶点，则G的总度数为__________，分枝点数为________________.
6设A、B为两个集合,A={1,2,4},B={3,4},则从AB＝_________________________;AB＝_________________________;A－B＝_____________________.
7.设R是集合A上的等价关系，则R所具有的关系的三个特性是__自反，对称，传递____________________,________________________,_______________________________.
8.设命题公式G＝(P(QR，则使公式G为真的解释有__________________________，_____________________________,__________________________.
9.设集合A＝{1,2,3,4},A上的关系R1={(1,4,(2,3,(3,2},R2={(2,1,(3,2,(4,3},则
R1R2=________________________,R2R1=____________________________,R12=________________________.
10.设有限集A,B，|A|=m,|B|=n,则||(AB|=_____________________________.11设A,B,R是三个集合，其中R是实数集，A={x|-1≤x≤1,xR},B={x|0≤x<2,xR},则A-B=__________________________,B-A=__________________________,A∩B=__________________________,.
13.设集合A＝{2,3,4,5,6}，R是A上的整除，则R以集合形式(列举法记为__________________________________________________________________.
14.设一阶逻辑公式G=xP(xxQ(x，则G的前束范式是_______________________________.
15.设G是具有8
