设集合A={x|x=（2n+1）180°，n∈Z}，与集合B={y|y=（4k±1）180°，n∈Z}之间的关系是______．
因为n∈Z，所以令n=2m，n=2m-1，
所以集合A={x|x=（2n+1）180°，n∈Z}={x|x=（4m+1）180°或x=（4m-1）180°，m∈Z}，
又因为集合B={y|y=（4k±1）180°，k∈Z}，
所以A=B．
故答案为：A=B．
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| Today, English is spoken in many countries. 1 English spoken in the UK is a little different from that in the USA in spelling, meaning, pronunciation, grammar, usage and so on. Sometimes, 2 English spoken in the UK is very different in every region (区域) 3 the country. Differences in spelling don't 4 speakers of British English from understanding the meanings of the words. 5 , they don't prevent speakers of American English from understanding the meanings either. 6 in spelling are not a big problem for even speakers of English as a 7 language. However, when different words in British English and American English are used to 8 the same thing 9 the same word has different meanings in British English and American English, sometimes people will not be understood if they don't know common differences between British English and American English in meanings and usages. Sometimes even Americans and British people do not 10 each other because of different word meanings. 11 , the British word "brolly" is an"umbrella" in America. And the British 12 potato chips "crisps". All of these differences led British writer George Bernard Shaw to 13 that Britain and America are two countries 14 by the same language! That's the reason why confusion or misunderstanding will be caused in some situations. Of course, such confusion will 15 happen to speakers of English as a second language. | ||||
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