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佛教怎样解答人类起源的问题?
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地球形成之后最初的人类,是从色界第六天的光音天而来,有关天人堕落人间之事,在《起世经》《大楼炭经》皆有记载。
编者按:人类从哪里来?这个问题延续了千百年,在各国文化中都有不同答案。中国古代有女娲造人的传说,基督教说是上帝创造了人类,进化论者认为人类是由古猿进化而来。那么,在佛教教义中,如何解答人类起源问题?
最初的人类是从色界第六天的光音天而来(图片来源:资料图片)
佛教不相信宇宙有个创造神,专门创造宇宙与人类的神权乃至祸福吉凶,是非善恶由神权所主宰,这一连串的邪说谬论,在目前的时代已逐渐被文明的人士唾弃,在欧美各国皆视为天方夜谭。
佛教相信:宇宙形态的变化,生命过程的流转,那是由于众生所造的&业力&,因而感召的结果。
至于生命在地球上的最初出现,佛教相信是由变化而来,下至单细胞的生物,上至人类,都是一样。
地球形成之后最初的人类,是从色界第六天的光音天而来,他们是飞空而来,天人的业报已尽,必然感召堕落,天人贪爱地球上的一种天然食物,吃了之后身体粗重、不能飞行,就在地球安居下来,这有关天人堕落人间之事,在《世纪经》《大楼炭经》《起世经》皆有记载。
实际上,天人的天福享尽,禅定一消失,必定又随业受报,要往生到哪一个世界去,就由自作的业力所支配,如是于十方世界循环不定,换句话说:这些天人在未生于色界第六天的光音天之前,就已造下生于光音天之业因,因而感召生于彼处,依此类推,在未感生于光音天之前亦有他们的世界,如是无止尽的生命历程,佛法称为生命是无始的,不是神权创造人类的,甚至生命所拥有的祸福吉凶乃至善恶之报也不是神权在支配驱使,而是众生自作自受,随自业自报,生命历程是无终的,是永恒不灭的,绝对不会断灭或被主宰,仅是随业受报,一世又一世周旋轮回罢了。
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48小时点击排行1/3,2/5,4/9,(),16/23,32/33如何解答?_百度作业帮
1/3,2/5,4/9,(),16/23,32/33如何解答?
1/3,2/5,4/9,(),16/23,32/33如何解答?
8/15分子.1.2.4.x.16.32.二倍,所以是8分母3.5.9.Y.23.333+2=55+4=99+6=1515+8=2323+10=33,分母各加2.4.6.8.10托福阅读真题:宇宙理论类题目如何解答?_新东方网
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11:23&&作者:富亦聪&&来源:新东方网&&字号:|
  日的托福阅读考试中出现了一道关于宇宙理论的题目:宇宙大爆炸,宇宙起源的两种学说,稳定宇宙和发展宇宙,大爆炸理论。他们之间共同承认膨胀。针对宇宙理论类题目考生们该如何作答?托福阅读中关于宇宙理论类的相关背景如何掌握呢?请看是新东方富亦聪老师的讲解:
  托福阅读真题再现:
  宇宙的两个理论,一个说物质会变化但总量不变,一个是会膨胀,最后说一个遥远的恒星的发现说明后一个理论更正确;
  新东方富亦聪解析托福阅读真题:
  天文主题文章的词汇专业性较强,尽量减少生词恐惧带来的内耗。另外,出现理论对比的文章,结构比较清晰,但要着重识别对理论内容的态度倾向。比如这篇文章讲的就是在大爆炸理论盛行之前,有一种与之替换的稳定宇宙理论。但最后,还是大爆炸理论占了上风。
  宇宙理论相关背景普及:
  a. Big Bang
  The Big Bang theory is the prevailing cosmological model for the early development of the universe. According to the theory, the Big Bang occurred approximately 13.82 billion years ago, which is thus considered the age of the universe. At this time, the universe was in an extremely hot and dense state and was expanding rapidly. After the initial expansion, the universe cooled sufficiently to allow the formation of subatomic particles, including protons, neutrons, and electrons. Though simple atomic nuclei formed within the first three minutes after the Big Bang, thousands of years passed before the first electrically neutral atoms formed. The majority of atoms that were produced by the Big Bang are hydrogen, along with helium and traces of lithium. Giant clouds of these primordial elements later coalesced through gravity to form stars and galaxies, and the heavier elements were synthesized either within stars or during supernovae.
  b. The steady state universe theory
  In cosmology, the Steady State theory is a now-obsolete theory and model alternative to the Big Bang theory of the universe's origin (the standard cosmological model). In steady state views, new matter is continuously created as the universe expands, thus adhering to the perfect cosmological principle.
  While the steady state model enjoyed some popularity in the first half of the 20th century, it is now rejected by the vast majority of professional cosmologists and other scientists, as the observational evidence points to a Big Bang-type cosmology and a finite age of the universe.
  c. Big Bang or Steady State?
  Creation of the Elements
  The 1930s was more a decade of consolidation than of revolutionary advance in cosmology. And in the early 1940s, world war limited cosmological advance. But the war that temporarily absorbed scientific resources also promoted technologies that would lead to fundamental scientific advances.
  Advances in nuclear physics helped transform cosmological speculations into quantitative calculations. This line of investigation, begun in the late 1940s, was at first pursued mainly by physicists, not astronomers. In the 1930s Georges Lema?tre had suggested that the universe might have originated when a primeval "cosmic egg" exploded in a spectacular fireworks, creating an expanding universe. Now physicists found plausible numbers for the cosmic abundances of different elements that would be created in an initial cosmic explosion. But the theory of an initial cosmic explosion was soon challenged by a new hypothesis—that the universe might be in a steady state after all.
  In 1946 the Ukrainian-born American physicist George Gamow considered how the early stage of an expanding universe would be a superhot stew of particles, and began to calculate what amounts of various chemical elements might be created under these conditions. Gamow was joined by Ralph Alpher, a graduate student at George Washington University, where Gamow taught, and by Robert Herman, an employee at the Johns Hopkins Applied Physics Laboratory, where Gamow consulted. Both Alpher and Herman were American-born sons of émigré Russian Jews.
  Gamow assumed expansion and cooling of a universe from an initial state of nearly infinite density and temperature. In that state all matter would have been protons, neutrons, and electrons merging in an ocean of high energy radiation. Gamow and Alpher called this hypothetical mixture "Ylem" (from a medieval word for matter). Alpher made detailed calculations of nuclear processes in this early universe. For his calculations he used some of the first electronic digital computers—developed during the war for computing, among other things, conditions inside a nuclear bomb blast. It seemed that elements could be built up as a particle captured neutrons one by one, in a sort of "nuclear cooking."
  The contribution of this theory was not to set forth a final solution but, no less important, to set forth a grand problem—what determined the cosmic abundance of the elements? Could the observed abundances be matched by calculations that applied the laws of physics to an early extremely hot dense phase of an expanding universe? Gamow did succeed in explaining the relative abundances of hydrogen and helium. Calculations roughly agreed with observations of stars—helium accounted for about a quarter of the mass of the universe and hydrogen accounted for nearly all the rest. However, attempts to make calculations for other elements failed to get a sensible answer for any element beyond helium. It seemed that piling more neutrons onto helium would hardly ever get you stable elements. Gamow joked that his theory should nevertheless be considered a success, since it did account for 99% of the matter in the universe.
  Indeed his theory was not wrong but only incomplete. Astrophysicists soon realized that if the heavier elements were not formed during the hot origin of the universe, they might be formed later on, in the interiors of stars. The theory depended on a special property of carbon, which British astronomer Fred Hoyle measured and found as predicted. Cosmology had entered the laboratory.
  The Steady-State Theory
  Hoyle's triumph in explaining how most elements could be created in stellar interiors fell outside the theory in which elements were created at the very start. It was interpreted as favoring a rival theory. And Hoyle did favor a rival theory, which he had played a large part in inventing and developing. In this theory the universe had always looked much as it does now. There never had been a "big bang"—a phrase that Hoyle invented in 1950, intending the nickname as pejorative.
  There is a charming story, not taken seriously by all historians, about how steady state theory began. The idea came in 1947, Hoyle claimed, when he and his fellow scientists Hermann Bondi and Tommy Gold went to a movie. The three knew each other from shared research on radar during World War II. Hoyle was versatile, undisci Bondi had a sharp and order Gold's daring physical imagination opened new perspectives. The movie was a ghost story that ended the same way it started. This got the three scientists thinking about a universe that was unchanging yet dynamic. According to Hoyle, "One tends to think of unchanging situations as being necessarily static. What the ghost-story film did sharply for all three of us was to remove this wrong notion. One can have unchanging situations that are dynamic, as for instance a smoothly flowing river." But how could the universe always look the same if it was always expanding? It did not take them long to see a possible answer—matter was continuously being created. Thus new stars and galaxies could form to fill the space left behind as the old ones moved apart. (You can read Gamow's verse about this idea here.)
  Drawings of an early and a later stage for two different models of an expanding universe. The left model obeys the cosmological principle, according to which the universe is homogenous and appears the same to an observer anywhere in the universe. The right model obeys the perfect cosmological principle, which adds to the cosmological principle the additional requirement that the universe be unchanged over time—new galaxies emerge continually within the expanding space.
  To many philosophical minds, the steady-state universe proposed by Hoyle, Bondi and Gold had a major advantage over the big-bang expanding universe. In their universe the overall density was kept always the same by the continuous creation of matter. In the big-bang universe with its radically changing density, various physical laws might not apply the same way at all times. It would be impossible to extrapolate with confidence from the present back to the super-dense origin of the universe.
  Steady-state theory also had an observational advantage over big-bang theory in 1948. The rate of expansion then observed, when calculated backward to an initial big bang, gave an age for the universe of only a few billion years—well below the known age of the solar system! That was certainly an embarrassment for the big bang theory.
  For some time cosmologists had measured ideas against a "cosmological principle," which asserted that the large-scale properties of the universe are independent of the location of the observer. In other words, any theory that put we humans at some special place (like the center of the universe) could be rejected out of hand. Bondi and Gold insisted that the universe is not only homogenous in space but also in time—it looks the same at any place and at any time. They grandly called this the "perfect cosmological principle," and insisted that theory should be deduced from the axiom that we are not at any special place in either space or time.
  Hoyle was less insistent that the perfect cosmological principle was a fundamental axiom. He preferred to have theory follow from a modification he proposed to Einstein's relativistic universe, adding the creation of matter. The two different steady-state theories had enough in common, however, to be considered one for most purposes.
  Much of the later development of steady-state theory came in response to criticism. In Great Britain, especially, scientists gave considerable attention to elaborating the theory. Their arguments were largely of a philosophical nature, with little appeal to observation.
  The cosmological debate acquired religious and political aspects. Pope Pious XII announced in 1952 that big-bang cosmology affirmed the notion of a transcendental creator and was in harmony with Christian dogma. Steady-state theory, denying any beginning or end to time, was in some minds loosely associated with atheism. Gamow even suggested steady-state theory was attached to the Communist Party line, although in fact Soviet astronomers rejected both steady-state and big-bang cosmologies as "idealistic" and unsound. Hoyle himself associated steady state theory with personal freedom and anti-communism.
  Astronomers in the United States found the steady-state theory attractive, but they took a pragmatic approach. The rival claims of big-bang and steady-state theory must be settled by observational tests. One test involved the ages of galaxies. In a steady state, with continuous creation of matter, there would be a mixture of young and old galaxies throughout the universe. In a big bang, with only an initial creation, galaxies would age with time. And astronomers could look back in time by looking at more distant galaxies, for observing a galaxy a billion light-years away meant seeing it in light that had left it a billion years ago. Observations reported in 1948 purported to find that more distant galaxies were indeed older. Score one for the big bang. Bondi and Gold reviewed the data carefully, and in 1954 they showed that the reported effect was spurious. Score one for steady state. The age test might be able to distinguish between the rival theories in principle, but in practice it could not.
  Another possible test involved the rate of expansion of the universe. In a big bang, the expan in a steady state universe it would remain constant. Data from the Mount Wilson Observatory seemed to favor the big bang, but not certainly enough to constitute a crucial test.
  Meanwhile there was a solution to the embarrassing calculation that put the age of a big-bang universe less than the age of the solar system. Walter Baade showed that estimates of the distances to galaxies had mixed together two different types of stars (as explained here). As a result, the size of the universe had been underestimated by about a factor of two. If galaxies were twice as distant as previously thought, then calculation with the observed rate of expansion gave an age of the universe twice as great as previously calculated — safely greater than the age of the solar system. That argument against the big-bang universe thus dissolved.
  The most serious challenge to steady-state theory came from the new science of radio astronomy. Fundamental knowledge in the techniques of detecting faint radio astronomy signals advanced greatly during World War II, especially with research on radar and especially in England. After the war, research programs at Cambridge, at Manchester, and at Sydney, Australia, built radio telescopes to detect signals from outer space. They dominated radio astronomy for the next decade.
  The program at Cambridge was led by Martin Ryle, who in 1974 would receive the Nobel Prize in physics for his overall contributions to radio astronomy. In 1951 Ryle believed that radio sources were located within our galaxy, and hence were of no cosmological interest. But over the next few years he became convinced that most of the radio sources he was detecting were extragalactic. His observations, then, could be used to test cosmological models. Ryle argued that his survey of almost 2,000 radio sources, completed in 1955, contradicted steady-state theory, because more distant/older sources seemed to be distributed differently from nearby ones. But he overstated the significance of his initial data. Only after more years of work would radio observations argue strongly against steady-state theory.
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明教小魔女怎样提高解题速度?
提问:级别:幼儿园来自:福建省
回答数:10浏览数:
怎样提高解题速度?
做理科题目,中等难度的大题一般要做十几二十几分钟,平时的解题速度就很慢,靠试时经常有几题完成不了。怎样提高解题速度,怎样训练自己才能提高解速度?
&提问时间: 09:47:42
最佳答案此答案已被选择为最佳答案,但并不代表问吧支持或赞同其观点
回答:级别:一级教员 22:51:32来自:安徽省滁州市
把所做的题分类,多总结各种题型的解法
提问者对答案的评价:
回答:级别:高二 10:48:37来自:四川省成都市
多练习一下,我做题的速度也不快,我们老师告诉过我说如果考试的时候作不完了,就把方程列在那里不计算了,正确的方程可以得2/3的分,可以节省很多时间!
回答:级别:一年级 11:38:54来自:甘肃省定西市
平时你多做练习,把这些典型例题的解题步骤记下.我想应该没问题了
回答:级别:幼儿园 22:17:42来自:广东省
解题速度=练+兴趣
练:就是做题,每天规定做几道题.规定时间内做.可以4、5道先.等解题提高了点后.就加量.久了就会提高的
兴趣:很多学生都觉得解决理科的题好烦.总是涉及很多知识.就会开始厌倦.看到题就没心思做下去.所以一定要培养弱科的学习兴趣.特别是理科.不得不去感兴趣.不然学起来是很吃力的.
回答:级别:三年级 20:21:59来自:中国
  高考是选拔性的考试,高考试题有一定难度,份量又重。要在限定的时间内完成高考试题殊不容易。因此,时间是非常宝贵的,要做完所有的题,特别是要想有时间检查,速度就成了非常重要的因素。
提高速度是有学问的。有的人欲速则不达,有的人又快又好。那么怎样才能提高速度呢?
首先,要冷静、保持正常的心态,不能一味求快,否则会使解题正确率下降,而且高考题都是有一定难度的,用时过少是很难审清题意,解出正确答案,那么就会使人紧张、着急、乱了分寸,最终反而降低解题速度,降低解题成功率,也就是所谓欲速则不达。在保持冷静的同时要有全局观,全面审题,务求解题思路正确,这是提高速度的前提。因为解题思路清楚了,解题自然又快又好,而若思路、方向错了,再快都没用,只会浪费时间,即使最终回到正确思路上来,题也已做了一半,自然无速度可言。
其次,对解题中常用的概念、公式、数据等应当熟悉,达到可直接带入的程度。否则,若有的公式不熟悉,要在考试时再推导得出又费时又易出错。当然最关键的是要记住有关概念、公式、原理的应用条件。另外,对那些常用又较复杂、难记的知识,平时就要弄懂、记清、记准、记牢,以便在解题过程中节约时间。
再次,要注意运用解题的技巧。在解计算题的过程中,要利用数学的简便算法,要利用分配律、交换律等规律,力求步骤简便、正确,解物理题时要善于运用各种守恒原理、图象来帮助解题。文科答卷要紧扣中心词汇,作出精要的答案,不要列写一大堆事实、现象,要言简意赅、简捷明了,自然就快了。
第四,要提高书写速度,书写要规范、清楚。另外平时还要注意提高生活节奏,加快思考、准备和做事的节奏,良好的生活和学习习惯对提高解题速度也是有帮助。
总之,要在高考中取得佳绩,就要设法在保持较高的解答正确率的情况下提高解题速度。下面以
下面以数学为例细讲 :
华罗庚先生认为:“学习数学而不做题,好比入宝山而空返。”这精辟地说明了解题的重要性。数学解题是数学内容与数学方法的统一,是理论与实践的论一。而解题速度直接影响解题的成败,决定解题速度主要是心理状态,知识技能,思维方法等三个主要方面,本文就提高解题速度作初步探讨。
一、调整心理状态,提高解题速度
1、克服思维定势,另辟解题蹊径
心理学研究表明:思维定势现象人人都有,所谓思维定势,就是指人们按一种固定的思路去考虑问题,有积极心理,也有消极心理作用,甚至造成负迁移,使思维受阻。
这四个数的大小。
这是一个比较几个分数大小的问题,绝大多数学生只知道常规方法先通分,化为同分母分数,再由分子的大小确定顺序。但本题各分母互质,通分时候将遇到较繁计算,如果打破常规,不循常法,实施“通分子”,再比较分母的大小确定顺序,便可很快地得到结果。∴
由此可见,克服思维定势,利用“通分子”是比较某些分数大小的一种捷径。2、 排除干扰因素,把握问题实质
为了考查学生的阅读审题能力和对数学知识的理解程度,数学试题尤其是选择题常可有意设置各种障碍和干扰因素。
例2 、任意调换五位数12345各位上的数字位置,所得五位数质数的个数是(
对此题,学生往往先考虑是否能获得质数,将1、3挑在个位上,逐个编排尝试,但这样做常难理头绪,使思路容易受阻,只要克服紧张焦急心理的影响,冷静地分析题意,把握住这个数的各位数字之和为15,因而不管如何调换数字位置,所得五位数均可被3整除,这样,立即排除题设中“任意调换”的干扰信息,而一口报出其答案为(D)
3、另外,情绪、兴趣、情感等心理因素都能成为思维障碍,影响解题速度。厌学的学生不会展开积极的思维,看见数学题则眉头皱,见到不熟悉的题更是心慌失措,更不会认真分析,数学题当然解不出来了。因此要重视对学生心理障碍及思维缺陷的分析和把握,并辅以有针对性的心理训练。
二、增强知识技能,提高解题速度
解题过程中灵活地利用某些技巧,对于运算的迅速和准确有很大作用,因而要引导学生善于发现和多用技巧。
1、运用“知识组块”增大思维跨度
解答选择题、填空题、是非题等题型的问题,只需直接写出结果,因此它可借助“知识组块”对解题步骤进行合并、省略、简化,从而增大思维跨度,提高解题速度。“知识组块”是指知识点通过知识间的联系,联结而成的知识网络,把每一个“知识组块”展开,都可以发现其中包含着一系列逻辑关系。例如围绕着余弦定理的三角变形的一个“知识组块”是,在 中
学生大脑里如果具有这样的“知识组块”,便可提高解答有关三角问题的速度。
例3、 的值为:
解:据上述“知识组块”中的(1),令 得
2、根据知识规律,简缩解题步骤
同一类型的数学问题,往往蕴含着共同的解题规律。根据这些规律就可以大大简缩解题步骤,提高解题速度,有时甚至可以一口报出答案。
例4.求证:
解此题,通常切化弦,再积化和差分别求出分子、分母的值推出结论,它的运算过程较繁。
若了解到:
则可根据(一)所揭示的规律,迅速地抓住题目的特征进行比较,可以发现所证等式左边具备应用(一)的部分形态,
于是可用组块补形的方法加以证明。
上述证明简捷清晰,它源于知识规律的获得和运用。
3、挖掘隐蔽条件,突破解题难关
具有一定难度的数学问题,往往含有隐蔽条件,如果能够挖掘这些隐蔽条件,就能越过“思维障碍”,突破解题难关,或者能够获得巧妙的解题方法,提高解题速度。
例5、甲、乙两队各出7名队员,按事先排好的顺序出场参加围棋擂台赛,双方先由1号队员比赛,负者被淘汰,胜者再与负方2号队负比赛,……直到有一方队员全部被淘汰为止,另一方获得胜利,形成一种比赛过程,那么所有可能出现的比赛过程的种数有多少?
对此题如果滞留在棋赛的各种胜负情况的考查上,那么思路就无法展开,如果能挖掘出该题隐蔽的一个数学模型:甲方获胜,由必胜7场,用7个“+”号表示,该方最多只能负6场,用6个“-”号表示,这样原问题就成了排列组合中,一排13个空格内画上7个“+”号的画法有多少种的问题了,甲方取胜得 种,再加上乙方取胜 种,因而可能出现的比赛过程为2 种。本题难点的突破,表现在从挖掘隐蔽条件到构造数学模型的飞跃上。
值得强调的是,在对于解题技巧的提炼,切忌一招一式、支离破碎,而要善 于引导学生深刻地理解寓于技巧中的重要的思想方法,并掌握类同于此的运算过程。
三、掌握直觉思维,提高解题速度
1、 通过直觉思维,简化推理过程
直觉思维是与逻辑思维相对应的,是未经考查推理而迅速对某些问题的结论作出大胆推测、设想的一种思维过程。在传统的解题教学中,比较强调逻辑思维的方向。爱因斯坦曾说过“真正可贵的因素是直觉。” 波利亚也曾指出:“直观的洞察和逻辑的证明是先知真理的两种不同方式,直观的洞察可能远远超前于逻辑的证明。”直觉思维具有直觉性、经验性和迅速性,直觉思维作出的判断具有模糊性和不可靠性。因此,在解答问题中凭借直觉作出判断,依靠验证才能作出肯定回答。
例6、已知 对定义域中一切 满足 ( 为正常数),求证 是周期函数。
分析:要证
为周期函数,则需证明存在常数 ,使 对定义域中一切 成立。这表明解题的关键在于直觉感知下T的取值.观察题的结构,发现与 类同,由 ,且 为 的一个周期,类比得出 的一个周期可能为4a,下面给予证明:
故4a是 的一个周期,
为周期函数.
2、进行整体分析、优化解题方法
所谓整体思维方法,就是对问题的整个系统进行研究的方法。它不从问题的各个细节着眼,而是注重纵观全局,着眼于问题的全貌或本质,是思维敏捷性的具体表现。由于整体分析,从问题的全局出发,把握了问题的全貌,容易揭示问题的本质,从而能够选择最优化的思路,最简捷的解题方法。
例7、设 是公差为-2的等差数列,如果 那么
解题时若孤立地看每一项,只好用基本量法引进首项后再用通项公式得前几项和公式,过程冗繁,如学生有整体意识, 观察到条件与结论均有: 项,将这两个33进行整体比较,设后者为M,则
分析:本题常见方法是用数学归纳法证明,但其过程较繁,
若记 ,构造 ,易知 ,则
从上两例看出,整体分析,简明扼要,化难为易.
3、使用逆向思维,促进求解转机
有些问题如果从正面硬拼,即使绞尽脑汁也一无所获,这时我们可从问题的反面入手,“从目标走开,转过头来倒着干。”这正如“退”是为“进”一样,我们暂时背离目标是为了最终达到目的。
例9 若方程 中至少有一个方程有实根,求m的范围.
分析:三个方程中至少有一个方程有实根的可能性有七种,要解七个不等式组,但如果从问题的反面去考虑问题,就只需考虑三个方程无实根这一种情况。
解: 如果三个方程均无实根,则
这个不等式组的解是
即当 时三个方程均无实根,那么,当 或 时三个方程至少有一个方程有实根.
例10 求 的展开式中各项的所有有理数系数的和.
对此题,若正面求得,须用二项式定理展开的计算求和,则不胜其烦,如果从反面思考,不展开二项式,以x=y=1代入求得二项式的各项系数之和,从中提出有理部分即得所求之值。
解:在原式中令,得 ,原式的展开式中各项系数和为
这是一个无理数,故知展开式中所有的有理数系数之和是零.
从上面两例可知,正难则反,逆向思考,可出奇制胜,马到功成!不失为一种行之有效的好方法。
结束语:影响解题速度的因素,有的属于心理状态,如克服思维定势、排除干扰因素(紧张焦急心理,往往是不能排除干扰因素的主要原因);有的是属于知识技能,如运用“知识组块”,根据知识规律,挖掘隐蔽条件;有的属于思维能力,如通过直觉思维,进行整体化析,使用逆向思维等。其中思维能力是影响解题速度的关键,知识技能是影响解题速度的根本,心理状态是影响解题速度的必要条件。当然,影响解题速度的“三要素”是互相影响的,是互相联系、互相促进的。如知识技能会影响思维能力的发挥;思维能力会影响知识技能的运用;思维能力和知识技能又会影响心理状态。为了提高学生的解题速度,以及让学生养成良好的心理品质,熟练地掌握知识技能,更要提高学生的思维能力。
该回答在 20:46:17由回答者修改过
回答:级别:幼儿园 00:01:52来自:山东省济宁市
1) 打乒乓球!真的,快速击球可以提高反应速度。
2) 系统训练!
3) 要相信自己能够做到!
我是一个5年没做过一点作业的学生,以上是我提速的秘诀。很管用。
回答:级别:幼儿园 22:47:40来自:中国
在考试时,我们常常感到时间很紧,试卷还没来得及做完,就到收卷时间了,虽然有些试题,只要再努一把力,我们是有可能做出来的。这其中的原因之一,就是解题速度太慢。
几乎每个学生都知道,要想取得好成绩,必须努力学习,只有加强练习,多做习题,才能熟能生巧。可是有些学生天天趴在那里做题,但解出的题量却不多,花了大量的时间,却没有解出大量的习题,难道不应找一找原因吗?何况,我们并不比别人的时间更多。试想,如果你的解题速度提高10倍,那会是怎样一种情景?解题速度提高10倍?可能吗?答案是肯定的,完全可能。关键在于你想与不想了。
那么,究竟怎样才能提高解题速度呢?
首先,应十分熟悉习题中所涉及的内容,做到概念清晰,对定义、公式、定理和规则非常熟悉。你应该知道,解题、做练习只是学习过程中的一个环节,而不是学习的全部,你不能为解题而解题。解题是为阅读服务的,是检查你是否读懂了教科书,是否深刻理解了其中的概念、定理、公式和规则,能否利用这些概念、定理、公式和规则解决实际问题。解题时,我们的概念越清晰,对公式、定理和规则越熟悉,解题速度就越快。因此,我们在解题之前,应通过阅读教科书和做简单的练习,先熟悉、记忆和辨别这些基本内容,正确理解其涵义的本质,接着马上就做后面所配的练习,一刻也不要停留。我指导学生按此方法学习,几乎所有的学生都大大提高了解题的速度,其效果非常之好。
其次,还要熟悉习题中所涉及到的以前学过的知识和与其他学科相关的知识。例如,有时候,我们遇到一道不会做的习题,不是我们没有学会现在所要学会的内容,而是要用到过去已经学过的一个公式,而我们却记得不很清楚了;或是数学题中要用到的一个物理概念,而我们对此已不是十分清晰了;或是需用到一个特殊的定理,而我们却从未学过,这样就使解题速度大为降低。这时我们应先补充一些必须补充的相关知识,弄清楚与题目相关的概念、公式或定理,然后再去解题,否则就是浪费时间,当然,解题速度就更无从谈起了。
第三,对基本的解题步骤和解题方法也要熟悉。解题的过程,是一个思维的过程。对一些基本的、常见的问题,前人已经总结出了一些基本的解题思路和常用的解题程序,我们一般只要顺着这些解题的思路,遵循这些解题的步骤,往往很容易找到习题的答案。否则,走了弯路就多花了时间。
第四,要学会归纳总结。在解过一定数量的习题之后,对所涉及到的知识、解题方法进行归纳总结,以便使解题思路更为清晰,就能达到举一反三的效果,对于类似的习题一目了然,可以节约大量的解题时间。
第五,应先易后难,逐步增加习题的难度。人们认识事物的过程都是从简单到复杂,一步一步由表及里地深入下去。一个人的能力也是通过锻炼逐步增长起来的。若简单的问题解多了,从而使概念清晰了,对公式、定理以及解题步骤熟悉了,解题时就会形成跳跃性思维,解题的速度就会大大提高。养成了习惯,遇到一般的难题,同样可以保持较高的解题速度。而我们有些学生不太重视这些基本的、简单的习题,认为没有必要花费时间去解这些简单的习题,结果是概念不清,公式、定理及解题步骤不熟,遇到稍难一些的题,就束手无策,解题速度就更不用说了。
其实,解简单容易的习题,并不一定比解一道复杂难题的劳动强度和效率低。比如,与一个人扛一大袋大米上五层楼相比,一个人拎一个小提包也上到五层楼当然要轻松得多。但是,如果扛米的人只上一次,而拎包的人要来回上下50次、甚至100次,那么,拎包人比扛米人的劳动强度大。所以在相同时间内,解50 道、100道简单题,可能要比解一道难题的劳动强度大。再如,若这袋大米的重量为 100千克,由于太重,超出了扛米人的能力,以至于扛米人费了九牛二虎之力,却没能扛到五楼,虽然劳动强度很大,却是劳而无功。而拎包人一次只拎10千克,15次就可以把150千克的大米拎到五楼,劳动强度也许并不很大,而效率之高却是不言而喻的。由此可见,去解一道难以解出的难题,不如去解30道稍微简单一些的习题,其收获也许会更大。因此,我们在学习时,应根据自己的能力,先去解那些看似简单,却很重要的习题,以不断提高解题速度和解题能力。随着速度和能力的提高,再逐渐增加难度,就会达到事半功倍的效果。
第六,认真、仔细地审题。对于一道具体的习题,解题时最重要的环节是审题。审题的第一步是读题,这是获取信息量和思考的过程。读题要慢,一边读,一边想,应特别注意每一句话的内在涵义,并从中找出隐含条件。读题一旦结束,哪些是已知条件?求解的结论是什么?还缺少哪些条件,可否从已知条件中推出?在你的脑海里,这些信息就应该已经结成了一张网,并有了初步的思路和解题方案,然后就是根据自己的思路,演算一遍,加以验证。有些学生没有养成读题、思考的习惯,心里着急,匆匆一看,就开始解题,结果常常是漏掉了一些信息,花了很长时间解不出来,还找不到原因,想快却慢了。很多时候学生来问问题,我和他一起读题,读到一半时,他说:“老师,我会了。”所以,在实际解题时,应特别注意,审题要认真、仔细。
第七,学会画图。画图是一个翻译的过程。读题时,若能根据题义,把对数学(或其他学科)语言的理解,画成分析图,就使题目变得形象、直观。这样就把解题时的抽象思维,变成了形象思维,从而降低了解题难度。有些题目,只要分析图一画出来,其中的关系就变得一目了然。尤其是对于几何题,包括解析几何题,若不会画图,有时简直是无从下手。所以,牢记各种题型的基本作图方法,牢记各种函数的图像和意义及演变过程和条件,对于提高解题速度非常重要。画图时应注意尽量画得准确。画图准确,有时能使你一眼就看出答案,再进一步去演算证实就可以了;反之,作图不准确,有时会将你引入歧途。
最后,对于常用的公式,如数学中的乘法公式、三角函数公式,常用的数字,如11~25的平方,特殊角的三角函数值,化学中常用元素的化学性质、化合价以及化学反应方程式等等,都要熟记在心,需用时信手拈来,则对提高演算速度极为有利。
总之,学习是一个不断深化的认识过程,解题只是学习的一个重要环节。你对学习的内容越熟悉,对基本解题思路和方法越熟悉,背熟的数字、公式越多,并能把局部与整体有机地结合为一体,形成了跳跃性思维,就可以大大加快解题速度
回答:级别:三年级 13:24:53来自:宁夏中卫市
最简单也是最难的即,努力做题,做大量的题,这样最容易提高速度。
回答:级别:幼儿园 10:27:42来自:河南省信阳市
常言道:熟能生巧,说明你对知识的掌握还不熟练,为什么老师解题都比较快,他们的知识都比较熟,且知识已经系统化,一看一般知道题目考察什么,鉴于此建议你:1巩固基础知识;2规定时间加强练习;3对老师讲解的要多总结重要的题,更重要的是方法!
回答:级别:三年级 17:49:11来自:安徽省滁州市
如何提高解题速度?
主持人:解题的速度跟不上,刚好有一个网友也问了,数学答题的速度太慢了,如何提高解题的速度?
熊跃农:提高解题的速度,基础知识要牢固,基本方法要熟练,思考问题要慎密,运算技能要扎实,书写表达要快捷。有的考生书写速度太慢,追求试卷的完美整洁,导致隐性失分,这是不可取的。应该不求完美,但求完成;不求整洁,但求准确。一份在规定时间内完成的答卷,只要书写的文字、式子、符号能看清楚就行了。
另外,草稿的使用也有讲究,可将草稿纸对折对折再对折,这样就有16个矩形区域,给每个区域编号就可对应16个题,这样做的好处在于检查某些运算有无错误时,不要到处找运算过程,浪费时间和精力。做解答题要先审题,理清思路,加强心算,争取一挥而就,下笔有神,落笔成功,尽量不用草稿纸。
主持人:现在是否可以通过限时的训练,自己给自己限定时间,做相应的题目,例如要找平时做题慢的原因,有可能是做解答题慢,这样是否有帮助?
熊跃农:这是非常好的办法,有的考生自己做了一个“错题本”,将历次考试中做错了的题都记录下来,针对这些错误的题进行限时训练,这是非常有效的训练。错题本基本上浓缩了高中数学的重点、难点、基点以及自己学习过程中的“盲点”。要安排足够时间整理知识方法,反思考卷,查漏补缺。
主持人:“错题本”记录的是考生个人失分的情况,结合“错题本”进行训练,是很好的办法
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