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随着常数 m 和 n 的变化,参数方程 x = sin(m · t), y = sin(n · t) 将会画出一系列漂亮的曲线。法国物理学家 Jules Antoine Lissajous 曾在 1857 年研究过这类曲线,因此人们把它叫做 Lissajous 曲线。我在 reddit 上看到了一个 Lissajous 曲线的动画演示,觉得看起来确实非常爽;但那个动画里没有解释曲线的生成方法,很多细节也有让人不太满意的地方,于是决定自己制作一个。 2016 年 7 月 30 日至 8 月 7 日,第 39 届欧洲杂耍大会(European Juggling Convention)在荷兰的阿尔梅勒举行, 8 月 3 日凌晨的搏击之夜(Fight Night)自然再度成为了众人关注的焦点——它是杂耍斗(combat juggling)这项运动最大的赛事。 杂耍斗是一种两人对战类的体育运动。 典型的一局比赛大致就像下面这样。 Read more… 下面这个趣题出自 Using your Head is Permitted 谜题站 2016 年 8 月的题目,稍有改动。 屋子里有若干个人,任意两个人都有恰好 1 个共同的朋友。 除了上图展示的情况之外,我们还能构造出很多别的同样满足要求的情况。 Read more… 无穷多个相同大小的正方形格子排成一排,向左右两边无限地延伸。 选择某个格子,保证该格子内至少含有 1 个原子。 初始时,某个格子里有 1 个原子。 Read more… 2016 年 IMO 的第 6 题(也就是第二天比赛的第 3 题)非常有趣,这恐怕算得上是近十年来 IMO 的所有题目中最有趣的题目之一。 证明:当 n 为奇数时, Geoff 一定有办法实现他的要求。

Revolucionando o mercado gráfico brasileiro | Printi 2011年硕士研究生入学统一考试考研数学考试大纲(1)_考研教育网 考研教育网 正保教育|考试大纲|招生简章|历年试题|考研调剂|考研复试|招生院校|查分|专题|学习卡|论坛|邮箱 考研网校|考研政治|考研英语|考研数学|专业课程|会计硕士|医学硕士|法律硕士|管理类硕士|免试|委培 考研政治 辅导课程|复习指导|历年试题|考试大纲|模拟试题|讨论专区|时事政治 您的位置:考研教育网> >考研数学>考试大纲 正文 2011年硕士研究生入学统一考试考研数学考试大纲(1) 相关热词:考研大纲2011,考研数学,考研公共课 转发分享: |更多 上一篇: 2011年硕士研究生入学统一考试考研数学考试大纲(3) 下一篇: 2011年硕士研究生入学统一考试考研数学考试大纲(2) 欢迎访问:考研网校考研论坛 相关新闻 2011年硕士研究生入学统一考试考研数学考试大纲(2) 精彩推荐 网站地图 Physics - spotlighting exceptional research Dave McClure Physics News - Physics News, Material Sciences, Science News, Physics Study reveals traits and evolutionary history of carnivorous bats (—A pair of researchers with the University of Washington has found similarities between different types of carnivorous bats compared to those that are insectivores or those that eat fruit, nectar or of course ... Monkeys and humans share staring behavior Following another's gaze is a hallmark of human learning and socialization from infancy to old age. Teen uses satellite imagery to discover possible ancient Mayan ruins (—William Gadoury, a 15 year old Mayan history enthusiast who lives in Saint-Jean-de-Matha in Lanaudière, Quebec, has, according to Le Journal de Montréal, used satellite imagery to make associations between ... Metal content in early galaxies challenges star forming theory An International team led by scientists at ETH Zurich in Switzerland used the W. 3-D Printing 101 Study suggests spawning at birth location boosts pike offspring success Legal culling of wolves increases poaching: study Power-ups for your browser All Psychology Careers | The Psychology Career and Education Center High Scalability - High Scalability Normal Distribution Calculator The Normal Distribution Calculator makes it easy to compute cumulative probability, given a normal random variable; and vice versa. For help in using the calculator, read the Frequently-Asked Questions or review the Sample Problems. To learn more about the normal distribution, go to Stat Trek's tutorial on the normal distribution. Note: The normal distribution table, found in the appendix of most statistics texts, is based on the standard normal distribution, which has a mean of 0 and a standard deviation of 1. To produce outputs from a standard normal distribution with this calculator, set the mean equal to 0 and the standard deviation equal to 1. Instructions: To find the answer to a frequently-asked question, simply click on the question. Why is the normal distribution so important? The normal distribution is important because it describes the statistical behavior of many real-world events. What is a standard normal distribution? There are an infinite number of normal distributions.

PennCalc Main/Calculus Single Variable Transcript of the Constitution of the United States - Official Text The Constitution of the United States: A Transcription Note: The following text is a transcription of the Constitution as it was inscribed by Jacob Shallus on parchment (the document on display in the Rotunda at the National Archives Museum.) Items that are hyperlinked have since been amended or superseded. We the People of the United States, in Order to form a more perfect Union, establish Justice, insure domestic Tranquility, provide for the common defence, promote the general Welfare, and secure the Blessings of Liberty to ourselves and our Posterity, do ordain and establish this Constitution for the United States of America. Article. Section. 1. All legislative Powers herein granted shall be vested in a Congress of the United States, which shall consist of a Senate and House of Representatives. Section. 2. When vacancies happen in the Representation from any State, the Executive Authority thereof shall issue Writs of Election to fill such Vacancies. Section. 3. Section. 4. Section. 5. G°.