tokenpocket最新版本|combination

作者: tokenpocket最新版本
2024-03-09 18:01:14

combination - 搜索词典

ination - 搜索词典 Rewards网页图片视频学术词典地图更多航班我的必应笔记本combination美 [ˌkɑmbɪˈneɪʃ(ə)n] 英 [ˌkɒmbɪˈneɪʃ(ə)n] n.结合；联合；混合；结合体网络组合；混合性皮肤；合并复数：combinations 搭配同义词v.+n.use combination,offer combination,discuss combinationadj.+n.possible combination,lethal combination,potent combination,deadly combinationn.mixture,grouping,blend,amalgamation,recipe权威英汉双解英汉英英网络释义combination显示所有例句n.1.[c]结合体；联合体；混合体two or more things joined or mixed together to form a single unitHis treatment was a combination of surgery, radiation and drugs.对他的治疗是把手术、放射和药物结合起来。What an unusual combination of flavours!多么与众不同的混合风味啊！Technology and good management. That's a winning combination(= one that will certainly be successful) .技术加良好的管理，这是取胜的组合。2.[u]结合；联合；混合the act of joining or mixing together two or more things to form a single unitThe firm is working on a new product in combination with several overseas partners.这家公司与几家海外合伙人在联合开发新产品。These paints can be used individually or in combination .这些涂料可单独或混合使用。3.[c]（用于开密码锁的）数码组合，字码组合a series of numbers or letters used to open a combination lockI can't remember the combination.我不记得密码锁的密码了。4.[pl]（旧时的）连裤内衣a piece of underwear covering the body and legs, worn in the pastn.1.结合,合并,混合,联合,配合,组合2.【数】组合;【化】化合(物);【矿】聚形;【语】组合词3.合作;共谋,同谋;同党4.〈英〉连裤衬衣5.附有旁座的摩托车6.暗码锁(的暗码)1.结合,合并,混合,联合,配合,组合2.【数】组合;【化】化合(物);【矿】聚形;【语】组合词3.合作;共谋,同谋;同党4.〈英〉连裤衬衣5.附有旁座的摩托车6.暗码锁(的暗码)n.1.something that combines several things; the process of putting, using, or mixing things together; using several types of treatment or drugs2.a series of numbers or letters used for operating a combination lock1.组合数学常用英文词汇_百度文库 ... proportion 比例 combination 组合 table 表格 ... wenku.baidu.com|基于4241个网页2.结合高二英语必修五单词列表_百度文库 ... tolerate v. 忍受 combination n. 结合 lack v. 缺乏 ... wenku.baidu.com|基于3486个网页3.混合性皮肤巴黎自助游攻略 - 穷游网 ... B平衡酸碱： alancing 混合性皮肤： Combination 持久性： Long lasting ... qz.qyer.com|基于1785个网页4.联合会计方面专业术语的英文翻译_百度文库 ... columnar journal 多栏日记账 combination 联合 commission 佣金 ... wenku.baidu.com|基于951个网页5.合并财务英语英汉对照表 (C) - MBA智库百科 ... co-manager 报销银团协理银行 combination 联合，合并 combination rate 联运费率 ... wiki.mbalib.com|基于946个网页6.化合英语四级词汇（整理版，16页，可直接打印） - 豆丁网 ... comb n. 梳子 combination n. 结合，联合；化合 combine vt. 使结合； …www.docin.com|基于677个网页7.结合，联合英语四级词汇（整理版，16页，可直接打印） - 豆丁网 ... comb n. 梳子 combination n. 结合，联合；化合 combine vt. 使结合； …www.docin.com|基于470个网页更多释义收起释义例句释义:全部全部,结合结合,联合联合,混合混合,结合体结合体,组合组合,混合性皮肤混合性皮肤,合并合并类别:全部全部,口语口语,书面语书面语,标题标题,技术技术来源:全部全部,字典字典,网络网络难度:全部全部,简单简单,中等中等,难难更多例句筛选收起例句筛选1.The operative treatment of Charcot arthropathy of the spine has conventionally been a combination of anterior and posterior surgery.脊柱关节病的传统一直是手术前，后组合。www.oaopdoc.com2.But, in combination with the bursting of the Shanghai bubble, they have been enough to turn perception around.但如果与上海股市泡沫的破裂结合来看，它们足以扭转人们的看法。www.ftchinese.com3.India's technology firms seem to be maturing, with a combination of fierce competition and rising wage costs putting pressure on profits.印度的技术公司似乎正在成熟，同时激烈的竞争和上涨的工资给利润造成压力。www.ecocn.org4.The combination of telling individuals that tobacco kills you and trying to intensify that fear with disgust-evoking images backfires.把告诉个人烟草害人和试图利用增强对反感形象的害怕的结合适得其反。www.hicoo.net5.The swine flu is a combination of bird, swine, and human influenzas. Health officials say people appear to have no immunity to it.新型猪流感病毒包含禽流感、普通猪流感以及人流感病毒片段。卫生部官员称人们显然对其没有免疫力。www.yappr.cn6.The planned merger with Iberia, the Spanish airline, looked as if it would be a winning combination a year ago when it was first mooted.在一年前，与西班牙伊比利亚航空公司（伊航）的合并计划被首次提出时，似乎真是一个完美的双赢组合。www.ecocn.org7.Although the team might have made correct decisions, the system's combination of technologies might be just too difficult to support.虽然项目组作出的决定可能都是正确的，系统的技术组合可能太难而难以支持。www.ibm.com8.The cause is not known, but it is thought to be the result of a combination of genetic and environmental factors.其原因仍不清楚，但被认为是遗传和环境因素共同作用的结果。www.who.int9.Indeed the finale of his Symphony no. 9 can be thought of as a sort of combination of sonata form and theme and variations.实际上，他的第九交响曲的最后一乐章可以被看作是奏鸣曲式、主题和变奏曲的结合体。www.bing.com10.Every sort of permutation and combination is possible in human nature.火的本性可能有各种交织和组合的情况。www.jukuu.com12345© 2024 Microsoft隐私声明和 Cookie法律声明广告帮

COMBINATION中文(简体)翻译：剑桥词典

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英语-中文（简体）

combination 在英语-中文（简体）词典中的翻译

combinationnoun uk

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/ˌkɒm.bɪˈneɪ.ʃən/ us

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B2 [ C or U ] the mixture you get when two or more things are combined

联合;混合;结合;综合

Strawberries and cream - a perfect combination.

草莓加奶油——完美的组合。

A combination of tiredness and boredom caused me to fall asleep.

疲倦而又无聊使我昏昏入睡。

This drug can be safely used in combination with other medicines.

这药可以同其他药物一起安全服用。

Her experience and energy are a winning combination (= a successful mixture) in business.

经验加干劲是她在生意上成功的秘诀。

[ C ] an arrangement in a particular order

组合

From the letters X Y Z, we can get three combinations of two letters: XY, XZ, and YZ.

由字母XYZ，我们可以得到3种两个字母的组合方式：XY，XZ和YZ。

[ C ] a set of letters or numbers in a particular order that can be used to open some types of locks

（用于开某些锁的）数码组合，密码

a combination lock

密码锁

更多范例减少例句Champagne and caviar make a wonderful combination.The school uses a combination of modern and traditional methods for teaching reading.She wears the most hideous colour combinations you could ever imagine.The bride's mother was wearing a horrible combination of green and yellow.That combination of tiredness and alcohol is extremely dangerous.

(combination在剑桥英语-中文（简体）词典的翻译 © Cambridge University Press)

combination的例句

combination

In the current study, however, the children are trained on two very distinct novel word-object combinations.

来自 Cambridge English Corpus

The effects of different combinations of investigations were analyzed in order to reflect alternative treatment pathways.

来自 Cambridge English Corpus

It was designed to facilitate the combination of qualitative methods with statistical analysis.

来自 Cambridge English Corpus

One special feature is for students to explore nontraditional sounds and sound combinations.

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The generalizations are advanced on the basis of statistical data from the population census of 1897 in combination with other quantitative and qualitative sources.

来自 Cambridge English Corpus

In summary, our results suggest that exposure to combinations of environmental stresses may increase the expression of additive genetic variability for fecundity.

来自 Cambridge English Corpus

To our knowledge, this is the first attempt to automatize the recognition of lf-instances among candidate combinations on a broader scale.

来自 Cambridge English Corpus

If afterimages are purely retinal in origin, then percepts that depend on binocular combination should not influence the afterimage.

来自 Cambridge English Corpus

示例中的观点不代表剑桥词典编辑、剑桥大学出版社和其许可证颁发者的观点。

combination的翻译

中文（繁体）

聯合, 混合, 結合…

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西班牙语

combinación, combinación [feminine]…

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combinação, combinação [feminine]…

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मिश्रण, जोडून, जोडणी…

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組み合わせ, 組（く）み合（あ）わせ, 組（く）み合（あ）わせ番号（ばんごう）…

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birleşim, karışım, terkip…

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combinaison [feminine], association [feminine], combinaison…

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combinació…

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combinatie…

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இரண்டு அல்லது அதற்கு மேற்பட்ட விஷயங்கள் இணைக்கப்படும்போது நீங்கள் பெறும் கலவை, ஒரு குறிப்பிட்ட வரிசையில் ஒரு ஏற்பாடு…

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(दो या अधिक चीज़ों का) मिश्रण, मेल, के साथ…

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સંયોજન, મિશ્રણ, મેચ…

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kombination, kode, kode-…

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kombination, förening…

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penggabungan, gabungan nombor…

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die Kombination…

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kombinasjon [masculine], kombinasjon, sammensetning…

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جوڑ, آمیزش, امتزاج…

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комбінація, поєднання…

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сочетание, код…

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కాంబినేషన్, రెండులేదా అంతకంటే ఎక్కువ అంశాల కలయిక వాళ్ళ ఏర్పడిన మిశ్రమ అంశం., ఒక ప్రత్యేక పద్దతి లో అమరిక…

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تَرْكيبة, خَليط…

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মিশ্রণ, সংমিশ্রণ, সংযুক্তি…

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kombinace, spojení…

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perpaduan, kombinasi…

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การรวมกัน, เลขรหัสปลดล็อค…

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sự kết hợp, dãy mã số mở ổ khoá…

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połączenie, kombinacja, szyfr…

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조화…

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combinazione…

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A flexitarian way of eating consists mainly of vegetarian food but with some meat.

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5分钟彻底了解排列组合 - 知乎

5分钟彻底了解排列组合 - 知乎首发于机器学习漫谈切换模式写文章登录/注册5分钟彻底了解排列组合小小神兽专注思辨性、偶尔小顽皮的杂食女青年看完本篇文章，保证你彻底理解「排列」「组合」这两个相爱相杀的概念到底有何区别。排列英文名叫 Arrangement 或者 Permutation，本文采用更 fancy 的 Permutation来表示排列，下文统称为 P。组合英文名叫 Combination，下文统称为 C。P 和 C 的本质区别在于：决策的顺序对结果有没有影响。下面举例说明现在有8个人，他们的名字分别为：AliceBobCatherineDonaldElizabethFloriaGatesHinton现在有 3 个奖杯，本别为 Golden 金牌，Silver 银牌，Bronze 铜牌。我们的任务是：将这 3 个奖牌颁发给 8 个人中的 3 个，先颁发金牌，再颁发银牌，再颁发铜牌。问颁发奖牌的不同方式总共有哪些？那么很明显，这是一个 Permutation 排列的问题，因为把金牌先颁给 Alice，再把银牌颁给 Bob，跟把金牌先颁给 Bob，再把银牌颁给 Alice 这是两种不同的颁奖方式。好了，现在假设我们先把金牌颁发给 Alice，再把银牌颁发给 Bob，再把铜牌颁发给 Catherine：第一步：颁发金牌 ️，可以在8个人中任选一个，有8种选择。A可以被替换为 B C D E F G H中的任何一个。第二步：颁发银牌，可以在除去已经获得金牌的人之外的7个人中任选一个，有7种选择。第三步：颁发铜牌，在已经获得金牌、银牌的两个人之外的6个人中任选一个，有6种选择。那么很明显，总共的颁奖方式有8 * 7 * 6 种以此类推，假如我们现在要颁发 8 个奖牌给 8个人，那么我们会按照上述方法，每次颁发一种奖牌，直到奖牌被颁发完为止，这样，颁发奖牌的方式总共有：8 * 7 * 6 * 5 * 4 * 3 * 2 * 1 种但是，我们只颁发 3 个奖牌就不颁发了呀，怎么才能在乘到 5 那里停止呢？很明显，摆脱 5 * 4 * 3 * 2 * 1 即可，我们的做法是：把这个尾巴除掉就行啦！也就是：这个公式相当于在说：我们只使用 8 个数字的前 3 个！那么，如果我们现在有 n 个运动员，要按顺序地颁发 k 个奖牌，有多少不同的颁奖方式呢？答案是：至此，我们得到：如果要想在 n 个物品中，按顺序的选择 k 个物品，那么选择的方式总共有这么多种：至此，排列的计算公式怎么来的应该清楚了吧。接下来讲组合同样还是颁奖，这次我们颁的不是金、银、铜牌，而是 3 个一模一样的可乐瓶，不好意思，主办方真的就是来搞笑的，可乐瓶真的 nobody cares，所以给谁先颁奖后颁奖，结果都是一样的，Alice 先颁发到一个可乐瓶、Bob 后拿到，跟 Bob先拿到一个可乐瓶、Alice后拿到，两种结果都是一样的。那么在 8 个人当中选 3 个人颁发一样的可乐瓶，有多少种颁发方法呢？在上面排列的基础上，也就是给三个人颁发的是不同的奖杯，最终选出的三个人，拿奖是有顺序的，也就是，最后计算出来的所有方法中，把三个奖杯的放置顺序进行了排列。但是现在，如果颁发的是可乐瓶，那么，获奖的顺序变得不再重要，谁先得，谁后得，结果都是一样的。上面排列的结果已经把不同颁发顺序视作不同颁发方法了，现在，3 个人中，不同的颁发顺序都是同一种！所以，我们只需要把「上一步排列获得的结果」除以「不同颁发顺序的总数」，得到的就是可乐瓶颁发方法的总数。不同颁发顺序的总数有 3！种所以，总共有这么多种：继续，如果要想在 n 个物品中，选择 k 个物品出来，选择的顺序无所谓，那么选择的方式总共有这么多种：C(n,k)也记作：ok，至此我想你们应该懂得排列跟组合的区别，以及他们的计算公式是怎么来的吧？如果对你有帮助，欢迎给我点赞编辑于 2019-10-21 10:36数学统计学通俗解释赞同 4547273 条评论分享喜欢收藏申请转载文章被以下专栏收录机器学习漫谈接地气地分享机器学习和跟数据打交道的那

组合（数学名词）_百度百科

学名词）_百度百科网页新闻贴吧知道网盘图片视频地图文库资讯采购百科百度首页登录注册进入词条全站搜索帮助首页秒懂百科特色百科知识专题加入百科百科团队权威合作下载百科APP个人中心组合是一个多义词，请在下列义项上选择浏览（共4个义项）展开添加义项组合播报讨论上传视频数学名词收藏查看我的收藏0有用+10本词条由“科普中国”科学百科词条编写与应用工作项目审核。组合（combination）是一个数学名词。一般地，从n个不同的元素中，任取m（m≤n）个元素为一组，叫作从n个不同元素中取出m个元素的一个组合。我们把有关求组合的个数的问题叫作组合问题。中文名组合外文名combination类型从不同元素中抽取部分元素的问题相关组合数、组合总数一级学科数学二级学科初等代数目录1组合定义2组合总数3重复组合组合定义播报编辑组合（combination），数学的重要概念之一。从n个不同元素中每次取出m个不同元素（0≤m≤n），不管其顺序合成一组，称为从n个元素中不重复地选取m个元素的一个组合。所有这样的组合的总数称为组合数，这个组合数的计算公式为或者n元集合A中不重复地抽取m个元素作成的一个组合实质上是A的一个m元子集合。如果给集A编序成为一个序集，那么A中抽取m个元素的一个组合对应于数段到序集A的一个确定的严格保序映射，组合数的常用符号还有 [1]组合总数播报编辑组合总数（total number of combinations）是一个正整数，指从n个不同元素里每次取出0个，1个，2个，…，n个不同元素的所有组合数的总和，即n元集合的组合总数是它的子集的个数。从n个不同元素中每次取出m个不同元素而形成的组合数的性质是：1、2、利用这两个性质，可化简组合数的计算及证明与组合数有关的问题。 [1]重复组合播报编辑重复组合（combination with repetiton）是一种特殊的组合。从n个不同元素中可重复地选取m个元素。不管其顺序合成一组，称为从n个元素中取m个元素的可重复组合。当且仅当所取的元素相同，且同一元素所取的次数相同，则两个重复组合相同。从n个不同元素中可重复地选出m个元素的不同组合种数记为或，且 [1]新手上路成长任务编辑入门编辑规则本人编辑我有疑问内容质疑在线客服官方贴吧意见反馈投诉建议举报不良信息未通过词条申诉投诉侵权信息封禁查询与解封©2024 Baidu 使用百度前必读 | 百科协议 | 隐私政策 | 百度百科合作平台 | 京ICP证030173号京公网安备110000020000

combination是什么意思_combination的翻译_音标_读音_用法_例句_爱词霸在线词典

ination是什么意思_combination的翻译_音标_读音_用法_例句_爱词霸在线词典首页翻译背单词写作校对词霸下载用户反馈专栏平台登录combination是什么意思_combination用英语怎么说_combination的翻译_combination翻译成_combination的中文意思_combination怎么读,combination的读音,combination的用法,combination的例句翻译人工翻译试试人工翻译翻译全文简明柯林斯牛津combinationCET4/CET6/考研/TOEFL/IELTS英 [ˌkɒmbɪˈneɪʃn]美 [ˌkɑːmbɪˈneɪʃn]释义n.结合（体）; 联合（体）点击人工翻译，了解更多人工释义词态变化复数: combinations;实用场景例句全部结合联合体密码组合His treatment was a combination of surgery, radiation and drugs.对他的治疗是把手术、放射和药物治疗结合为一体。牛津词典What an unusual combination of flavours!多么与众不同的混合风味啊！牛津词典Technology and good management. That's a winning combination (= one that will certainly be successful) .技术加良好的管理，这是取胜的组合。牛津词典The firm is working on a new product in combination with several overseas partners.这家公司与几家海外合伙人在联合开发新产品。牛津词典These paints can be used individually or in combination.这些涂料可单独或混合使用。牛津词典I can't remember the combination.我不记得密码锁的数码组合了。牛津词典...a fantastic combination of colours.多种颜色的绝妙混合柯林斯高阶英语词典...the combination of science and art.科学与艺术的结合柯林斯高阶英语词典Each of the outstanding automobile design is the perfect combination of aesthetics and engineering.每一辆杰出的汽车设计都是美学与工程学的完美结合.期刊摘选A Source code for a combination Lock using a Pic 16 F 84.源代码的组合锁使用照片16F84.期刊摘选I think a combination of both was at play.我认为二者都在起作用.期刊摘选Ride south from a main secondary combination of the three quadrangles.由坐北朝南一主二次的三个四合院组合而成.期刊摘选Suggestion: to improve the science of the training and the combination the training and medical treating.建议: 进一步加强训练的科学性,加强训科医三结合.期刊摘选These players made a very good combination.这些运动员配合得很好.《现代英汉综合大词典》It is a developmental aesthetics with the combination and statics.茶艺美学是动静结合、不断发展的美学.期刊摘选John and Tom are a strong combination at football.在足球场上,约翰和汤姆是强强组合.期刊摘选Methods: Combination of the intracellular injection and electron microscope techniques were used.方法: 采用细胞内注射,电镜连续切片技术.期刊摘选You cannot use indentation in combination with other tags, as box or code.缩进标记不能和其他标记组合使用, 例如框体或者代码.期刊摘选Firmware is a combination of software and hardware.固件是由软件和硬件合成的.期刊摘选The function of the original CPU + CPLD combination can be realized by one FPGA chip.采用可编程逻辑器件就能弥补上述缺点,把原来CPU+CPLD硬件组合形式实现的功能仅用一块FPGA芯片来实现.期刊摘选And thensolved key questions such as work flow design, heterogeneous database combination, network security etc.解决了业务工作流程设计、多部门数据库资源整合等关键问题.期刊摘选He carried on the business in combination with his friends.他与朋友们合伙做生意.《简明英汉词典》Their method of negotiating is a combination of the carrot and the stick.他们谈判的方法是软硬兼施.《简明英汉词典》The materials can be used singly or in combination.这些材料可以单独使用也可以混合用.《简明英汉词典》The orchestra played with a winning combination of gusto and precision.这个管弦乐队在演奏热情与精确性之间达到了水乳交融的境界.《简明英汉词典》The book is anodd combination of audacity andintense conservatism.那本书很怪,所谈内容既很大胆,又非常保守.《现代英汉综合大词典》His treatment was a combination of surgery, radiation and drugs.对他的治疗是把手术、放射和药物治疗结合为一体。《牛津高阶英汉双解词典》a harmonious combination of colours协调的色彩搭配《牛津高阶英汉双解词典》收起实用场景例句真题例句全部四级六级高考考研What matters, she added, is a combination of what people bring in with them, and what they find there.出自-2016年6月阅读原文Longevity results from a combination of mental and physical health.出自-2016年6月阅读原文Forty-eight of the students received instruction in study skills only, whereas the others attended a combination of study skills sessions and classes in which they learned about the growth mind-set and how to apply it to schoolwork.出自-2016年12月阅读原文From the first paragraph, we learn that America's recession is the result of a combination of causes.出自-2013年6月阅读原文Citing the work of psychologists and cognitive (认知的)scientists, Leslie criticizes the received wisdom that academic success is the result of a combination of intellectual talent and hard work.2017年12月四级真题（第二套）阅读 Section BI love the colonial fabrics, all the silver work, the furnishings, the combination of elegance and simplicity.2017年12月四级真题（第二套）听力 Section CA lot of times people are not really aware of the impact they have, or the fact that taking them in combination with other medications might put you at increased risk for something that you wouldn’t otherwise being countering or be at risk for.出自-2016年6月听力原文Now what’s interesting about the theory is what do you have if you only have one out of three or two out of three? What do you have and how is it different if you have a different two out of three? What’s interesting about this kind of theorizing is it gives rise to many different combinations that can be quite interesting when you break them down and start to look at them carefully.出自-2016年12月听力原文For others, a combination of mass transit and private transportation may be desirable.出自-2015年12月听力原文Stacked near the checkout counters, and as colorful as a Fisher-Price toy, is a not-so-serious-looking power tool: a battery-operated saw-and-drill combination.出自-2013年6月阅读原文My colleagues and I are studying something called augmented reality (a field of computer research dealing with the combination of real-world and virtual reality)," said Christopher Dede, professor in learning technologies at Harvard University, "Alien Contact," for example, is an exercise developed for middle-school students who use hand-held devices that can determine their location出自-2013年6月阅读原文A lot of times people are not really aware of the impact they have, or the fact that taking them in combination with other medications might put you at increased risk for something that you wouldn't otherwise being countering or be at risk for.2016年6月六级真题（第二套）听力 Section BBeyond revealing population-wide patterns, the right combination of data and analysis can also help individuals identify unique characteristics of their own behavior, including conditions that could indicate the need for some form of intervention-such as 2018年12月六级真题（第一套）阅读 Section CEarlier this month a separate study found that a combination of climate change and industrial fishing is threatening the krill (磷虾) population in Antarctic waters, with a potentially disastrous impact on whales, seals and penguins.2019年12月六级真题（第三套）阅读 Section CMultiples can be deployed in combination for more complex missions than could be achieved by one CubeSat alone.2019年6月六级真题（第三套）阅读 Section BThe combination of computational power and engineering advances will eventually enable lower-cost in-home care for the disabled, widespread use of driverless cars that may reduce drunk- and distracted-driving accidents and countless home and service-indus2016年6月六级真题（第二套）阅读 Section AThe resulting steel appears to achieve a combination of strength and toughness that is comparable to that of modern steels that are very rich in alloy content and, therefore, very expensive.2019年6月六级真题（第三套）阅读 Section AWhen taking any drug, you should ask your doctor whether drinking alcohol could be dangerous in combination with the medicine.2017年12月六级真题（第二套）听力 Section CAfter running hundreds of tests, the researchers noted that the monkeys would go for the higher values more than half the time, indicating that they were performing a calculation, not just memorizing the value of each combination.2019年高考英语全国卷3 阅读理解阅读D 原文But now, with the combination of a better price point and a generally fresher product, they can stay in business.2018年高考英语江苏卷阅读理解阅读C 原文Students are provided with a combination for their room door locks upon check-in.2015年高考英语天津卷阅读理解阅读A 原文The building has a remarkable shape and looks like a combination of "blocks".2015年高考英语湖北卷阅读理解阅读C 原文The fee is $25 to change a room combination.2015年高考英语天津卷阅读理解阅读A 原文The office of residence life may change the door lock combination at any time at the expense of the resident if it is found that the student has shared the combination with others.2015年高考英语天津卷阅读理解阅读A 原文This combination of healing myself and healing the world struck me as the perfect solution.2017年高考英语天津卷完形填空原文Toknow magazine is a big hit in the world of children's publishing, bringing a unique combination of challenging ideas and good fun to young fans every month.2017年高考英语北京卷阅读理解阅读B 原文When individuals are involved in deliberate play, they experiment with new or different combinations of behaviors, but not necessarily in the most effective way to improve performance.2015年高考英语上海卷阅读理解阅读表达原文With their patience and efforts, they successfully developed a combination of artificial breeding and natural reproduction.2019年高考英语江苏卷完形填空原文During the Depression and the war, Americans had learned to live with less, and that restraint, in combination with the postwar confidence in the future, made small, efficient housing positively stylish.2011年考研真题（英语二）阅读理解 Section ⅡTheir reactions may be a complex combination of instant reflexes, input from past driving experiences, and what their eyes and ears tell them in that moment.2020年考研真题（英语一）翻译 Section Ⅲ收起真题例句英英释义Noun1. a collection of things that have been combined; an assemblage of separate parts or qualities2. a coordinated sequence of chess moves3. a sequence of numbers or letters that opens a combination lock;"he forgot the combination to the safe"4. a group of people (often temporary) having a common purpose;"they were a winning combination"5. an alliance of people or corporations or countries for a special purpose (formerly to achieve some antisocial end but now for general political or economic purposes)6. the act of arranging elements into specified groups without regard to order7. the act of combining things to form a new whole收起英英释义词根词缀后缀: -ation1. 表名词,"行为,过程,结果"; 2. 注：如果加在y结尾的单词后通常为去掉y加上ication.n.revocation 废弃,取消revoc=revoke废除+ation行为,过程,结果→n.废弃,取消combination 结合,联合;化合;团体;组合数码combine联合+ation行为,过程,结果→n.结合,联合;化合;团体;组合数码confirmation 证实,确定;确认confirm证实+ation行为,过程,结果→n.证实,确定;确认determination 决心;决定;确定determine决心+ation行为,过程,结果→n.决心;决定;确定excitation 刺激;激动;激发excite使兴奋+ation行为,过程,结果→n.刺激;激动;激发exclamation 叫喊;感叹exclaim叫喊;感叹+ation行为,过程,结果→n.叫喊;感叹explanation 解释,解说,说明,辩解ex出去+plan明白+ation行为,过程,结果→使其明白→解释,解说generalization 一般化;概括,综合generalize一般的+ation行为,过程,结果→n.一般化;概括,综合imagination 想象[力];空想,幻觉;想象出来的事物imagine设想+ation行为,过程,结果→n.想象[力];空想,幻觉;想象出来的事物inclination 倾斜,弯曲,倾度,倾向,爱好incline倾斜;偏向+ation行为,过程,结果→n.倾斜,弯曲,倾度,倾向,爱好lamentation 悲痛,哀悼,痛哭lament悲伤,哀悼+ation行为,过程,结果→n.悲痛,哀悼,痛哭limitation 限制,局限性limit限制+ation行为,过程,结果→n.限制,局限性obligation 义务,责任oblige迫使,责成+ation行为,过程,结果→n.义务,责任presentation 介绍;赠送;呈现present赠送+ation行为,过程,结果→n.介绍;赠送;呈现provocation 激怒provoc=provoke激怒+ation行为,过程,结果→n.激怒recommendation 推荐,介绍[信],劝告,建议recommend赞扬;推荐+ation行为,过程,结果→n.推荐,介绍[信],劝告,建议representation 描写;陈述;代表represent描述,表示+ation行为,过程,结果→n.描写;陈述;代表reservation 保留,保留意见;预定,预订reserve保留,储备;预定+ation行为,过程,结果→reservation保留starvation 饥饿starve使饿死+ation行为,过程,结果→n.饥饿同义词辨析mixture, blend, combination, compound, composite这些名词均含"混合"之意。mixture：普通用词，指不同类种、性质不同的事物的混合。blend：侧重混合成分之间的类似和整个混合物的统一性。combination：指相混元素的紧密结合，但不一定的是融合。compound：特指两种或多种元素构成的化合物。composite：通常可与compound换用，但倾向于指人为的或偶然的结合或凑合。同义词n.混合mixturemixaggregationsynthesisblendamalgamationcompositeamalgamcompoundhybridn.组合,配合groupingassortmentn.结合,合并joiningconjunctionconglomerationadmixturecoalescencecomminglingassemblageminglementminglingblendingintermixturen.联合affiliationconcernleagueunionalignmentassociationblocbrotherhoodcartelfederationcoalitionfactionjointalliancepartnershipmerger其他释义conspiracyconjuncturefusiontissuecompositionmedleyconnection反义词n.结合;团结separation其他释义separation行业词典体育混合队数学组合法律联合联营药学联合释义词态变化实用场景例句真题例句英英释义词根词缀同义词辨析同义词反义词行

Combinations and Permutations

What's the Difference?

In English we use the word "combination" loosely, without thinking if the order of things is important. In other words:

"My fruit salad is a combination of apples, grapes and bananas" We don't care what order the fruits are in, they could also be "bananas, grapes and apples" or "grapes, apples and bananas", its the same fruit salad.

"The combination to the safe is 472". Now we do care about the order. "724" won't work, nor will "247". It has to be exactly 4-7-2.

So, in Mathematics we use more precise language:

When the order doesn't matter, it is a Combination.

When the order does matter it is a Permutation.

So, we should really call this a "Permutation Lock"!

In other words:

A Permutation is an ordered Combination.

To help you to remember, think "Permutation ... Position"

Permutations

There are basically two types of permutation:

Repetition is Allowed: such as the lock above. It could be "333".

No Repetition: for example the first three people in a running race. You can't be first and second.

1. Permutations with Repetition

These are the easiest to calculate.

When a thing has n different types ... we have n choices each time!

For example: choosing 3 of those things, the permutations are:

n × n × n (n multiplied 3 times)

More generally: choosing r of something that has n different types, the permutations are:

n × n × ... (r times)

(In other words, there are n possibilities for the first choice, THEN there are n possibilites for the second choice, and so on, multplying each time.)

Which is easier to write down using an exponent of r:

n × n × ... (r times) = nr

Example: in the lock above, there are 10 numbers to choose from (0,1,2,3,4,5,6,7,8,9) and we choose 3 of them:

10 × 10 × ... (3 times) = 103 = 1,000 permutations

So, the formula is simply:

where n is the number of things to choose from,

and we choose r of them,

repetition is allowed,

and order matters.

2. Permutations without Repetition

In this case, we have to reduce the number of available choices each time.

Example: what order could 16 pool balls be in?

After choosing, say, number "14" we can't choose it again.

So, our first choice has 16 possibilites, and our next choice has 15 possibilities, then 14, 13, 12, 11, ... etc. And the total permutations are:

16 × 15 × 14 × 13 × ... = 20,922,789,888,000

But maybe we don't want to choose them all, just 3 of them, and that is then:

16 × 15 × 14 = 3,360

In other words, there are 3,360 different ways that 3 pool balls could be arranged out of 16 balls.

Without repetition our choices get reduced each time.

But how do we write that mathematically? Answer: we use the "factorial function"

The factorial function (symbol: !) just means to multiply a series of descending natural numbers. Examples:

4! = 4 × 3 × 2 × 1 = 24

7! = 7 × 6 × 5 × 4 × 3 × 2 × 1 = 5,040

1! = 1

Note: it is generally agreed that 0! = 1. It may seem funny that multiplying no numbers together gets us 1, but it helps simplify a lot of equations.

So, when we want to select all of the billiard balls the permutations are:

16! = 20,922,789,888,000

But when we want to select just 3 we don't want to multiply after 14. How do we do that? There is a neat trick: we divide by 13!

16 × 15 × 14 × 13 × 12 × ...13 × 12 × ... = 16 × 15 × 14

That was neat: the 13 × 12 × ... etc gets "cancelled out", leaving only 16 × 15 × 14.

The formula is written:

n!(n − r)!

where n is the number of things to choose from,

and we choose r of them,

no repetitions,

order matters.

Example Our "order of 3 out of 16 pool balls example" is:

16!(16−3)! = 16!13! = 20,922,789,888,0006,227,020,800 = 3,360

(which is just the same as: 16 × 15 × 14 = 3,360)

Example: How many ways can first and second place be awarded to 10 people?

10!(10−2)! = 10!8! = 3,628,80040,320 = 90

(which is just the same as: 10 × 9 = 90)

Notation

Instead of writing the whole formula, people use different notations such as these:

P(n,r) = nPr = nPr = n!(n−r)!

Examples:

P(10,2) = 90

10P2 = 90

Combinations

There are also two types of combinations (remember the order does not matter now):

Repetition is Allowed: such as coins in your pocket (5,5,5,10,10)

No Repetition: such as lottery numbers (2,14,15,27,30,33)

1. Combinations with Repetition

Actually, these are the hardest to explain, so we will come back to this later.

2. Combinations without Repetition

This is how lotteries work. The numbers are drawn one at a time, and if we have the lucky numbers (no matter what order) we win!

The easiest way to explain it is to:

assume that the order does matter (ie permutations),

then alter it so the order does not matter.

Going back to our pool ball example, let's say we just want to know which 3 pool balls are chosen, not the order.

We already know that 3 out of 16 gave us 3,360 permutations.

But many of those are the same to us now, because we don't care what order!

For example, let us say balls 1, 2 and 3 are chosen. These are the possibilites:

Order does matter

Order doesn't matter

1 2 3

1 3 2

2 1 3

2 3 1

3 1 2

3 2 1

1 2 3

So, the permutations have 6 times as many possibilites.

In fact there is an easy way to work out how many ways "1 2 3" could be placed in order, and we have already talked about it. The answer is:

3! = 3 × 2 × 1 = 6

(Another example: 4 things can be placed in 4! = 4 × 3 × 2 × 1 = 24 different ways, try it for yourself!)

So we adjust our permutations formula to reduce it by how many ways the objects could be in order (because we aren't interested in their order any more):

n!(n−r)! x 1r! = n!r!(n−r)!

That formula is so important it is often just written in big parentheses like this:

n!r!(n−r)! = (nr)

where n is the number of things to choose from,

and we choose r of them,

no repetition,

order doesn't matter.

It is often called "n choose r" (such as "16 choose 3")

And is also known as the Binomial Coefficient.

Notation

All these notations mean "n choose r":

C(n,r) = nCr = nCr = (nr) = n!r!(n−r)!

Just remember the formula:

n!r!(n − r)!

Example: Pool Balls (without order)

So, our pool ball example (now without order) is:

16!3!(16−3)!

= 16!3! × 13!

= 20,922,789,888,0006 × 6,227,020,800

= 560

Notice the formula 16!3! × 13! gives the same answer as 16!13! × 3!

So choosing 3 balls out of 16, or choosing 13 balls out of 16, have the same number of combinations:

16!3!(16−3)! = 16!13!(16−13)! = 16!3! × 13! = 560

In fact the formula is nice and symmetrical:

n!r!(n−r)! = (nr) = (nn−r)

Also, knowing that 16!/13! reduces to 16×15×14, we can save lots of calculation by doing it this way:

16×15×143×2×1

= 33606

= 560

Pascal's Triangle

We can also use Pascal's Triangle to find the values. Go down to row "n" (the top row is 0), and then along "r" places and the value there is our answer. Here is an extract showing row 16:

1 14 91 364 ...

1 15 105 455 1365 ...

1 16 120 560 1820 4368 ...

1. Combinations with Repetition

OK, now we can tackle this one ...

Let us say there are five flavors of icecream: banana, chocolate, lemon, strawberry and vanilla.

We can have three scoops. How many variations will there be?

Let's use letters for the flavors: {b, c, l, s, v}. Example selections include

{c, c, c} (3 scoops of chocolate)

{b, l, v} (one each of banana, lemon and vanilla)

{b, v, v} (one of banana, two of vanilla)

(And just to be clear: There are n=5 things to choose from, we choose r=3 of them,

order does not matter, and we can repeat!)

Now, I can't describe directly to you how to calculate this, but I can show you a special technique that lets you work it out.

Think about the ice cream being in boxes, we could say "move past the first box, then take 3 scoops, then move along 3 more boxes to the end" and we will have 3 scoops of chocolate!

So it is like we are ordering a robot to get our ice cream, but it doesn't change anything, we still get what we want.

We can write this down as (arrow means move, circle means scoop).

In fact the three examples above can be written like this:

{c, c, c} (3 scoops of chocolate):

{b, l, v} (one each of banana, lemon and vanilla):

{b, v, v} (one of banana, two of vanilla):

So instead of worrying about different flavors, we have a simpler question: "how many different ways can we arrange arrows and circles?"

Notice that there are always 3 circles (3 scoops of ice cream) and 4 arrows (we need to move 4 times to go from the 1st to 5th container).

So (being general here) there are r + (n−1) positions, and we want to choose r of them to have circles.

This is like saying "we have r + (n−1) pool balls and want to choose r of them". In other words it is now like the pool balls question, but with slightly changed numbers. And we can write it like this:

(r + n − 1)!r!(n − 1)! = (r + n − 1r)

where n is the number of things to choose from,

and we choose r of them

repetition allowed,

order doesn't matter.

Interestingly, we can look at the arrows instead of the circles, and say "we have r + (n−1) positions and want to choose (n−1) of them to have arrows", and the answer is the same:

(r + n − 1)!r!(n − 1)! = (r + n − 1r) = (r + n − 1n − 1)

So, what about our example, what is the answer?

(3+5−1)!3!(5−1)! = 7!3!4! = 50406×24 = 35

There are 35 ways of having 3 scoops from five flavors of icecream.

In Conclusion

Phew, that was a lot to absorb, so maybe you could read it again to be sure!

But knowing how these formulas work is only half the battle. Figuring out how to interpret a real world situation can be quite hard.

But at least you now know the 4 variations of "Order does/does not matter" and "Repeats are/are not allowed":

Repeats allowed

No Repeats

Permutations (order matters):

n!(n − r)!

Combinations (order doesn't matter):

(r + n − 1)!r!(n − 1)!

n!r!(n − r)!

708, 1482, 709, 1483, 747, 1484, 748, 749, 1485, 750

Activity: Subsets

Combinations and Permutations Calculator

Pascal's Triangle

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combination 在英語-中文（繁體）詞典中的翻譯

combinationnoun uk

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/ˌkɒm.bɪˈneɪ.ʃən/ us

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/ˌkɑːm.bəˈneɪ.ʃən/

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B2 [ C or U ] the mixture you get when two or more things are combined

聯合;混合;結合;綜合

Strawberries and cream - a perfect combination.

草莓加鮮奶油——完美的組合。

A combination of tiredness and boredom caused me to fall asleep.

疲倦而又無聊使我昏昏入睡。

This drug can be safely used in combination with other medicines.

這藥可以與其他藥物一起安全服用。

Her experience and energy are a winning combination (= a successful mixture) in business.

經驗加勁頭是她在生意上成功的秘訣。

[ C ] an arrangement in a particular order

組合

From the letters X Y Z, we can get three combinations of two letters: XY, XZ, and YZ.

由字母XYZ，我們可以得到三種兩個字母的組合方式：XY，XZ和YZ。

[ C ] a set of letters or numbers in a particular order that can be used to open some types of locks

（用於開某些鎖的）數碼組合，密碼

a combination lock

密碼鎖

更多範例减少例句Champagne and caviar make a wonderful combination.The school uses a combination of modern and traditional methods for teaching reading.She wears the most hideous colour combinations you could ever imagine.The bride's mother was wearing a horrible combination of green and yellow.That combination of tiredness and alcohol is extremely dangerous.

(combination在劍橋英語-中文（繁體）詞典的翻譯 © Cambridge University Press)

combination的例句

combination

A balanced combination of declarative and imperative languages is desirable for implementing multi-agent systems.

來自 Cambridge English Corpus

It is a problem that most electroacoustic educators seek to address in combination with the provision of extensive practical composition skills.

來自 Cambridge English Corpus

Such summation occurs for all combinations of directions and determines the time course of relative probabilities for combinations.

來自 Cambridge English Corpus

If afterimages are purely retinal in origin, then percepts that depend on binocular combination should not influence the afterimage.

來自 Cambridge English Corpus

Varying combinations of muscle groups were stimulated and foot switches were used to trigger each channel at the appropriate period of the gait cycle.

來自 Cambridge English Corpus

The performance source data may thus be analysed from several perspectives based on differing quantities and combinations of attributes.

來自 Cambridge English Corpus

The generalizations are advanced on the basis of statistical data from the population census of 1897 in combination with other quantitative and qualitative sources.

來自 Cambridge English Corpus

In this context heterogeneity may be induced by a combination of host behaviour, host genetics and past or current experience of infection.

來自 Cambridge English Corpus

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combination的翻譯

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联合, 混合, 结合…

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การรวมกัน, เลขรหัสปลดล็อค…

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combinazione…

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在英語詞典中查看 combination 的釋義

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A flexitarian way of eating consists mainly of vegetarian food but with some meat.

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如何理解 IB 数学中的排列组合公式 - 知乎

如何理解 IB 数学中的排列组合公式 - 知乎首发于IB 数学切换模式写文章登录/注册如何理解 IB 数学中的排列组合公式浣熊数学加拿大大不列颠哥伦比亚大学工程博士排列组合，在英文数学中叫 Permutation and Combination，运算起来常用首字母 P 和 C 表示，单看不难。但一到综合问题中，就会有很多个 P 和很多个 C，中间还常用加减乘除号连接，很多人一学就蒙，一算就算重算漏。书上的中等难度的题举例如下：如何解决“一学就蒙，一算就错”这个问题呢？我觉得大家可以先不必着急死记硬背公式，先用小的数字+几个故事理解一下这些公式怎么来的、适用于哪些问题，就容易学懂了。一：P 的由来所谓排列组合，排列在组合之前，咱们要聊的第一个概念是“排列”，排列的英文是 Permutation 或者 Arrangement，因此在数学符号中，用 P 或者 A 表示都可以，二者意思完全一样。我们常见的 P 右边会跟两个数字（或字母），右下角的数字 n 表示总数，右上角的数字 m 表示抽出的个数。整个符号的意思是“从 n 个人中，有顺序地抽出 m 个人的抽法数”，可以读作“P n 抽 m”。。那么，到底什么叫做有顺序的？我们来举个数字很小的例子：比如：班里有三名同学，成绩前两名有几种可能性？咱们可以用乘法原理：选第一名有 3 种可能性，选第二名有 2 中可能性，因为第一名那个人不可能同时又是第二名了，将这两步相乘起来。（如果你不太理解乘法原理，可以看看下图直观列举的表示。）这个公式需要注意的是：虽然书上每次讲到这个公式时一般以阶乘（factorial）的形式给出，但实际计算中，往往不用阶乘。我的记法是：从大的数字开始往小乘，乘“小的数字那么多”个。二：C 的由来咱们聊的第二个概念是“组合”，它比排列更常用，组合的英文是 Combination，因此在数学符号中用 C 表示，美国和英国教材中，也常用“长括号”表示组合数。我们常见的 C 右边会跟两个数字（或字母），右下角的数字 n 表示总数，右上角的数字 m 表示抽出的个数。整个符号的意思是“从 n 个人中，不计顺序地抽出 m 个人的抽法数”，可以读作“C n 抽 m”。那么，到底什么叫做不计顺序的？我们也来举个例子：比如：班里有三名同学，选出两名代表参加年级会议有几种选法？哈哈，这就可以用到之前排列数的结论了！就让刚才的第一名和第二名去参加会议。但是，对于参加会议来说，谁是第一谁是第二不重要呀！因此我把原图的红色和蓝色都涂成了黑色，以示无区别。（如下图）至此，第二步中，第一种和第三种都是 A、B 的组合，完全一样，就会有一些算重的，至于有多少个算重，取决于抽出个数 m 的全排列种数，即 m 的阶乘。（如果你不太理解哪些算重了，可以仔细看看下图中箭头所指的对应关系）于是，组合数公式就是在排列数公式上除以一个 m！。但实际计算中，往往不用阶乘。我的记法是：从大的数字开始往小乘，乘“小的数字那么多”个，再除以“小的数字开始往小乘，乘小的数字那么多个”。三：组合数的公式直观解释组合公式Ⅰ：这个公式课内和竞赛都会常常用到。我在刚学的时候把它联想成“做值日”问题，四个同学中，选三名同学做值日就相当于选一名同学放学直接回家。比如，班里有 A、B、C、D 四个同学，每天要选出三个同学做值日，有几种选法？这个问题对于学过排列组合的同学自然非常简单了，就是 C 4 抽 3，但是，假如问一个没学过排列组合的人，他会怎么想呢？如果想 ABC，ACD……这种就会比较难想，不如去想它的反面：选Ａ、B、C 或 D 放学直接回家，总共就四种。这就能直观的理解这个公式了。这个公式对于运算 C 10 抽 8 这样的组合数时非常有用，直接转化成 C 10 抽 2 来计算。组合公式Ⅱ：这个公式课内会提到，但不要求熟练掌握，竞赛会常用。可以把它联想成“约妹子看电影”问题，看看在四个妹子中，想约两个妹子有几种约法。如果四个人都是普通朋友，看作是相同的 A、B、C、D，那自然有 C 4 抽 2 =6 种约法。下面我们来点刺激的：假如这四个人中有一个是你女朋友，她最特殊，你会先问她来不来：①如果她来，但你还想一共约两个妹子（手动滑稽），那么就需要在其他三个妹子中再约一个，有 C 3 抽 1 种方法；②如果她不来，那你就需要在其他三个妹子中再约两个，有 C 3 抽 2 种方法。两类相加，表示的意义就是从 4 个妹子中约两个妹子的情况总数，即公式成立。这个公式对于处理两个组合数相加问题非常有用，落实在计算上，我把它总结成口诀：上面的数字取大的，底下的数字加一。组合公式Ⅲ这个公式课内和竞赛都会常常用到。我把它叫做抓兔子问题，想象一个笼子里有两只兔子，抓出来的话有几种抓法？第一种方法是我去笼子里抓，我在抓的时候就想好是抓 1 只还是抓 2 只，或是抓 0 只（即不抓）。由于先想好了这一点，就会有 C 2 抽 1 和 C 2 抽 2 这些组合数，分别表示按“抓一只”、“抓两只” 分类，每类的情况数；第二种情况是我把笼子打开，让每只兔子自己选择跳出来或是不跳出来（2 种可能性），每只兔子都是独立的个体，所以可以用乘法原理，总共的情况数是 n 个 2 相乘，即 2 的 n 次方。两种方法都表示“兔子出来的情况数”，因此一样，即公式得以解释。这个公式对于处理一系列“底下相同的”组合数相加的问题非常好用，大大节省计算量。而且它与集合、二项式定理等中学数学知识紧密相连，需深入理解。组合公式Ⅳ这个公式一般在竞赛中会出现。我把它叫做火车头问题：抽出的一些元素，总有一个打头的，称为火车头，它也是火车的一节，只不过是特殊的一节。具体来讲，比如说你要在 A、B、C、D、E 这 5 个小球中抽取 3 个小球，咱们可以按“哪个小球是第一个”分类第一类：A 为火车头，那么还需在后面四个小球中抽取两个小球；第二类：B 为火车头，那么还需在后面三个小球中抽取两个小球；第三类：C 为火车头，那么还需在后面两个小球中抽取两个小球。至于 D 或 E 开头的，就不足“三节车厢”了，故不计算。我们把之前说的三类加起来，就直观地理解了这个公式。这个公式对于处理一系列“上面相同的”组合数相加的问题非常好用，大大节省计算量。记忆方法是：和为上面下面都加一。组合公式Ⅴ这个公式是一个相加和相乘结合的公式，看似复杂，但并不难理解。我对它的理解是：可以想象成班里选几名学生，分男女选和不分男女选情况数一样。比如说，咱们假设班里有 7 名学生，4 男 3 女。如果选出三个人参加竞赛有几种选法？首先容易想到的是 C 7 抽 3 =35。没错，不过咱们还有一个思路，就是按“男女各多少人”分类讨论。第一类：0 男 3 女，分别抽取，再乘起来。第二类：1 男 2 女，分别抽取，再乘起来。第三类：2 男 1 女，分别抽取，再乘起来。第四类：3 男 0 女，分别抽取，再乘起来。这四类是互不重叠的，可用加法原理将其相加。原公式就得以直观理解。好啦，上面 5 个公式都可以代数证明，也可按照我举得例子通俗理解，如果这二者你都很清楚，那排列组合就能融会贯通了。本文详细讲了五个常用排列组合公式的理解。那么，如何把这些公式用在 IB 数学的难题上，我会在暑假班的课上详细讲解，欢迎私信我了解详情。发布于 2020-05-20 11:41排列组合数学组合数学（Combinatorics）赞同 373 条评论分享喜欢收藏申请转载文章被以下专栏收录IB 数学国际文凭大学预

在数学中，combination和permutation的理论和实用层面的区别？ - 知乎

在数学中，combination和permutation的理论和实用层面的区别？ - 知乎首页知乎知学堂发现等你来答切换模式登录/注册数学在数学中，combination和permutation的理论和实用层面的区别？刚才考试下来，满怀信心的我发现分数不理想，好多题错在combination和permutation用错了，想问这两个区别是什么？？关注者4被浏览13,620关注问题写回答邀请回答好问题 1添加评论分享2 个回答默认排序知乎用户数竞生。排列与组合自己在实际应用中更多用于估算理论概率，同时也与binomial theorem相关联。区别的话，combination不关心排列顺序，permutation关心排列顺序。比如ABC里排列两个元素，就只有A&B，A&C，B&C三种组合，就有AB，BA，AC，CA，BC，CB六种。发布于 2018-04-14 10:35赞同 82 条评论分享收藏喜欢收起请填写真实姓名关注Permutation and Combination (Definition, Formulas and Examples)大致来说，就是说permutation是将列表里的元素以某种方式按顺序排列出来，比如所有参赛选手里出现一二三等奖的所有可能组合方式。而combination则不在乎这样的顺序，比如所有初赛选手中，成功晋级的选手的所有可能的组合方式。更简单的来说，对于前者来说： ABC， ACB， BCA， BAC， CAB， CBA算六种排列方式；而后者只算一种。发布于 2022-11-21 00:38赞同添加评论分享收藏喜欢收起