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1.
中考内容要求实数与代数式所考查的知识有:有理数,倒数,相反数,绝对值,数轴的运用,实数的大小比较,乘方,科学记数法,有效数字,二次根式,实数的估算,列代数式,解释代数式,求代数式的值,探求数与式的规律.  相似文献   

2.
在中学,乃至大学的数学,都应该提倡“形数结合”,解析几何的诞生正是形数结合的光辉范例,在解析几何中,我们都知道,通过量(坐标)的演算,给许多几何问题提供了准确而又普遍的解法;反过来,给数与算式赋以适当的几何意义,又可借助图形的几何性质和直观形象,使困难的问题迎刃而解,同时,图形生动鲜明的形象,既便于理解又易于记忆,因此,这借几何直观解决问题的方法,倍受广大师生的青睐,近年来,出现了不少这方面的好文章,对数学的教学和传播起了很大的推动作用,然而,图形的描绘,显然不可能达到100%的精确,特别是较为复杂的图形;图形的多  相似文献   

3.
境由心生     
在现实生活中,有人总是企盼没有的,却忘了现成的,追求遥远的,却无视身边的永无止境的物质追求,让人变得贪婪;盲目的攀比,让人抱怨生活的不公境由心生,心情不好,就会失去一次次微笑着感受人生的喜悦,就会失去不少在情绪乐观时可以获得成功的机会……其实,在这个纷繁复杂、充满诱惑的社会,不羡慕别人,不轻贱目己,过自己喜欢过的日子,就是最好的日子,活自己喜欢的活法,就是最好的活法,按自己的天性度过自己的时日,就是天堂般的日子!  相似文献   

4.
我与珠心算     
提起珠心算,我想说的太多了。刚进一年级实验班,第一件让我傻眼的事就是珠心算了。当老师将小小的算盘轻轻放在我的面前时,我吓坏了,我的爸爸、妈妈都是会计,这可是大人们用的东西呀,我的天,我才几岁呀。刚开始练的时候,我的手不听话,不是多带珠就是少拨珠,我手用力,脚用力,浑身上下都用力,都不行,急得我眼里那些不争气的小水滴一个劲儿往下掉。这时,一只温暖的手轻轻地抚在我的头上,睁眼一看,一双慈爱的目光,温和地看着我,是张老师。她不慌不忙地对我说:“眼泪只会让你丧失信心,珠心算不是一两天就能练好的,只要你天天认真去练,就像你练钢琴一样,你一定会学好的。今天你为它流泪,明天你会为能应用它而骄傲的。”老师的话使我平静了。在以后的日子里,我不再急躁,而是跟在老师的后面一步一步地练,老师布置的作业我总是多练几遍,功夫不负有心人,经过半年时间的苦练,我的珠算水平已经突飞猛进了,手像在算盘上飞舞一样,连做会计的爸爸、妈妈也比不上我的速度,心算的速度快得令爸爸、妈妈、爷爷、奶奶刮目相看,终于,被老师选为小选手。又经过半年的苦练,我终于和其他三名同学代表如皋去南通参加比赛,我获得了听心算满分,个人全能三等奖好成绩。当登上领奖台,捧着金灿...  相似文献   

5.
吴英 《数学通讯》2011,(7):79-80
求最值,一直是高考的重点,求解的方法很多,有配方法,判别式法,不等式法,换元法,导数法等等,对于特定的题目选择合适的方法,有利于解题速度的提高,有利于解题结论正确性的提高.  相似文献   

6.
作为高中生 ,要想具备科学精神和创新思维习惯 ,可能有很多途径 ,其中有一条重要途径 ,成为众多成功的经验之谈 ,那就是论文写作 .一篇论文 ,或者介绍自己的学习心得 ,或者阐述自己的学习成果 ,或者归纳自己的解题经验 ,或者表达自己的某种想法 ,或者解答别人提出的问题 ,或者提出问题引发同仁讨论 ,你都必须有自己的思考 :首先是价值判断 ,认为你的所思所写有自己的东西 ,能够反映自己的水平 ,别人读后可以从中获益 ;其次 ,你必须把要写的东西弄明白 ,这就要广泛地收集材料 ,进行必要的推理 ,还要向老师请教与同学磋商 ;其三 ,论点清楚了 ,…  相似文献   

7.
[考试内容及考试要求]考试内容:平面及其基本性质,平面图形直观图的画法,平行直线,直线和平面平行的判定与性质,直线和平面垂直的判定,三垂线定理及其逆定理,两个平面的位置关系,空间向量及其加法、减法与数乘.空间向量的坐标表示,空间向量的数量积,直线的方向向量,异面直线所成的角,异面直线的公垂线,异面直线的距离,直线和平面垂直的性质,平面的法向量,点到平面的距离,直线和平面所成的角,向量在平面内的射影,平行平面的判定和性质,平行平面间的距离,二面角及其平面角,两个平面垂直的判定和性质,多面体、正多面体、棱柱、棱锥、球.考试要…  相似文献   

8.
优选法是一种科学方法,特别是它的思想方法——重实践,抓主要矛盾,以辩证唯物主义的哲学思想为指南,用理论联系实际的内容,深入浅出地引出既简单又通俗易懂的多种计算方法,使工农兵易于掌握,因此,优选法的推广和应用,深受广大工农兵的欢迎,取得了可喜的成果.但是,任何新生事物都是在斗争中产生、在斗争中发展的.所以,努力学习马列主义、毛泽东思想,提高路线斗争觉悟,在实践中分析各种矛盾的内在联系,抓准主要矛盾,是推广应用优选法的根本.  相似文献   

9.
过程参数未知时的连续检验问题   总被引:3,自引:0,他引:3  
对连续检验问题,Page(Page,1954)提出的累积和控制图(CUSUM)已被证明在检测小的漂移时效果很好,然而,当受控过程的参数未知时,CUSUM的应用受到限制,Quensenberyy(1991)提出用变换的方法将观测值中的未知参数消去,在原假设“过程保持一致”成立的条件下,变换得到的Q统计量为独立同分布的标准正态变量,这里有二个问题:问题之一是,如果过程中有一漂移发生,变换得到的Q统计量的分布就很复杂,漂移对Q统计量的均值的影响是非时间齐次的,随着过程的推移,漂移对Q的均值的影响越来越小,因此,基于Q统计量的检验问题与一般的连续检验问题是不同的,好的检验方法应将这种不同反映出来,因此,基一种基于Q的新的累积和检验统计量,模拟结果显示,这种统计量的效果是不错的,问题之二是,当过程方差未知时,Q统计量的值的计算很难,它需要计算t分布的分布函数和正态分布函数的逆函数,这在实际使用中几乎是做不到的,本文提出一种近似方法,它不需计算复杂的分布函数,而是给出近拟服从标准正态分布的统计量为作为检验统计量,模拟研究的结果显示,这种近似的效果很好,它的各项指标与精确方法的相应指标非常接近。  相似文献   

10.
不难验证,选择适当的空间直角坐标系,正四面体的四个顶点的坐标就可以设为:(a,a,a),(a,-a,-a),(-a,a,-a),(-a,-a,a),其中a〉0. 利用距离公式得:正四面体的棱长为2√2a. 利用上述正四面体顶点坐标的巧妙设法,本文给出四面体中的几个有趣的定值,供参考.  相似文献   

11.
We use the bifurcation method of dynamical systems to study the (2+1)‐dimensional Broer–Kau–Kupershmidt equation. We obtain some new nonlinear wave solutions, which contain solitary wave solutions, blow‐up wave solutions, periodic smooth wave solutions, periodic blow‐up wave solutions, and kink wave solutions. When the initial value vary, we also show the convergence of certain solutions, such as the solitary wave solutions converge to the kink wave solutions and the periodic blow‐up wave solutions converge to the solitary wave solutions. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

12.
首先给出了运输问题最优解的相关概念,将最优解扩展到广义范畴,提出狭义多重最优解和广义多重最优解的概念及其区别.然后给出了惟一最优解、多重最优解、广义有限多重最优解、广义无限多重最优解的判定定理及其证明过程.最后推导出了狭义有限多重最优解个数下限和广义有限多重最优解个数上限的计算公式,并举例验证了结论的正确性.  相似文献   

13.
In this paper, we use the bifurcation method of dynamical systems to study the periodic wave solutions and their limits for the modified Kd V–KP equations. Some explicit periodic wave solutions are obtained. These solutions contain smooth periodic wave solutions and periodic blow-up solutions. Their limits contain solitary wave solutions, periodic wave solutions, kink wave solutions and unbounded solutions.  相似文献   

14.
We obtain closed-form exact solutions to the 1 + 1 Born–Infeld equation arising in nonlinear electrodynamics. In particular, we obtain general traveling wave solutions of one wave variable, solutions of two wave variables, similarity solutions, multiplicatively separable solutions, and additively separable solutions. Then, putting the Born–Infeld model into correspondence with the minimal surface equation using a Wick rotation, we are able to construct complex helicoid solutions, transformed catenoid solutions, and complex analogues of Scherk’s first and second surfaces. Some of the obtained solutions are new, whereas others are generalizations of solutions in the literature. These exact solutions demonstrate the fact that solutions to the Born–Infeld model can exhibit a variety of behaviors. Exploiting the integrability of the Born–Infeld equation, the solutions are constructed elegantly, without the need for complicated analytical algorithms.  相似文献   

15.
In this paper, we study solution structures of the following generalized Lennard-Jones system in R~n,x=(-α/|x|~(α+2)+β/|x|~(β+2))x,with 0 α β. Considering periodic solutions with zero angular momentum, we prove that the corresponding problem degenerates to 1-dimensional and possesses infinitely many periodic solutions which must be oscillating line solutions or constant solutions. Considering solutions with non-zero angular momentum, we compute Morse indices of the circular solutions first, and then apply the mountain pass theorem to show the existence of non-circular solutions with non-zero topological degrees. We further prove that besides circular solutions the system possesses in fact countably many periodic solutions with arbitrarily large topological degree, infinitely many quasi-periodic solutions, and infinitely many asymptotic solutions.  相似文献   

16.
In this paper, we investigated vector equilibrium problems and gave the scalarization results for weakly efficient solutions, Henig efficient solutions, and globally efficient solutions to the vector equilibrium problems without the convexity assumption. Using nonsmooth analysis and the scalarization results, we provided the necessary conditions for weakly efficient solutions, Henig efficient solutions, globally efficient solutions, and superefficient solutions to vector equilibrium problems. By the assumption of convexity, we gave sufficient conditions for those solutions. As applications, we gave the necessary and sufficient conditions for corresponding solutions to vector variational inequalities and vector optimization problems.  相似文献   

17.
In this paper, we use the bifurcation method of dynamical systems to study the traveling wave solutions for the Davey–Stewartson equation. A number of traveling wave solutions are obtained. Those solutions contain explicit periodic wave solutions, periodic blow‐up wave solutions, unbounded wave solutions, kink profile solitary wave solutions, and solitary wave solutions. Relations of the traveling wave solutions are given. Some previous results are extended. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

18.
A new algebraic method is devised to uniformly construct a series of new travelling wave solutions for two variant Boussinesq equations. The solutions obtained in this paper include soliton solutions, rational solutions, triangular periodic solutions, Jacobi and Weierstrass doubly periodic wave solutions. Among them, the Jacobi elliptic periodic wave solutions exactly degenerate to the soliton solutions at a certain limit condition. Compared with most existing tanh methods, the proposed method gives new and more general solutions. More importantly, the method provides a guideline to classify the various types of the solution according to some parameters.  相似文献   

19.
In this letter, a new Riccati equation expansion method is presented for constructing exact travelling-wave solutions of nonlinear partial differential equations. The main idea of this method is to take full advantage of the solutions of the Riccati equation to construct exact travelling-wave solutions of nonlinear partial differential equations. As a result, some more generalized solutions, which contain triangular periodic solutions, exp function solutions and the soliton-like solutions, are obtained.  相似文献   

20.
In this paper, by means of the Jacobi elliptic function method, exact double periodic wave solutions and solitary wave solutions of a nonlinear evolution equation are presented. It can be shown that not only the obtained solitary wave solutions have the property of loop-shaped, cusp-shaped and hump-shaped for different values of parameters, but also different types of double periodic wave solutions are possible, namely periodic loop-shaped wave solutions, periodic hump-shaped wave solutions or periodic cusp-shaped wave solutions. Furthermore, periodic loop-shaped wave solutions will be degenerated to loop-shaped solitary wave solutions for the same values of parameters. So do cusp-shaped solutions and hump-shaped solutions. All these solutions are new and first reported here.  相似文献   

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