设A,B为两个有限集,讨论cardA,cardB,CARD[A交B】CARD【A并B】四个数值之间的关系.急

设A,B为两个有限集,讨论cardA,cardB,CARD[A交B】CARD【A并B】四个数值之间的关系.急 he is going to ________ his teacher a post carda.buy b.visit c.turn Let's give a birthday cardA,he B,they C,she D,her 设cardA=∝,B是A可数子集,card（A-B)是否可数?并解释.谢谢,急用考试啊 ( )1.He __ cards.I collect carda,__.A.collect,too B.collects,either C.collects,too(选择) I've just got a postcard from my pen friend.Let me have a look.Wow,( )nice cardA.what B.what a C.how D.why Let us give 空格 a birthday cardA.he B.her C.she D.they怎么书上有一句Let us give him a computer game 设A,B为群G的有限子群,证明|A|·|B|=|AB|·|A∩B| 3．设A,B为任意两个事件,则（　 　） A.B.C.D. 设A,B为两个事件,0 已知关于X的方程ax2+bx+c=o(a不等于0）的两个实数根为1和-1,那么a+B+C=______.a-b+c=___本人理解有限…… ...几道数学题.大家来帮个忙哈~1 设A=(1,2,3),试问M={X/X属于A}与N={X/X包含于A}有什么不同?2 设B,C均为有限集,B中元素的个数为m,C中元素的个数为n,且n>m,若A包含于B,A包含于CA中元素最少有几个?A中的 设A,B为两个集合,如果有A∩B=A∩C,且A∪B=A∪C,证明B=C. 设a,b是非零实数,则y=a/|a|+|b|/b+c/|c|可能取值的集合 是有限集 无限集 还是空集?为什么请尽快 一小时之内有分加 英语翻译3.What”s this ——It‘s ( ) ID cardA.an B.a C.the 4.Good afteroon,Kate.How are you?--------( )A.Im OK.B.I'm not good C.Thank you D.Good afternoon 英语翻译3.What”s this ——It‘s ( ) ID cardA.an B.a C.the 4.Good afteroon,Kate.How are you?--------( )A.Im OK.B.I'm not good C.Thank you D.Good afternoon 1.jacky is ____ of the winsA younger B the youngest C the younger D young2.last teacher's day the teachers receive a box ____ cardA was filled with B full of C fill with D fulled with 设有理数a、b、c满足a+b+c=0,abc大于0讨论a、b、c中正数的个数