浅谈激发技校生语文学习兴趣的方法

题目：（满分14分）已知曲线Cn：x^2-2nx＋y^2=0（n=1,2,…）.从点P（-1,0）向曲线Cn引斜率为kn（kn〉0）的切线lm切点为Pn（xn,yn）. （1）求数列{xn}与{yn}的通项公式;（2）证明：x1·x3·x5…x2n-1〈√1-xn/1＋xn〈√2 sinxn/yn.     

条件x+y=1下1/xn+λ/yn最小值的简单求法

文 [1]给出了条件 x+ y=1下 1xn+ λyn的最小值定理 ,并利用 (a2 + b2 ) (c2 + d2 )≥ (ac+ bd) 2 (a,b,c,d∈ (0 ,+∞ )和待定系数法证明之 .定理　已知 x,y,λ∈ (0 ,+∞ )且 x+ y=1,则当且仅当 y∶ x=λ1n+ 1 时 ,1xn+ λyn(n∈N* )取最小值 ,最小值为 (1+ λ1n+ 1 ) n+ 1 .本文给出定理的一个简单证明 .证明　∵x,y,λ∈ (0 ,+∞ ) ,n∈ N* ,且x+ y=1,∴ 1xn+ λyn=(1xn+ λyn) (x+ y) n =(1xn+λyn) (C0nxn+ C1 nxn-1 y+ C2nxn-2 y2 +… + Crnxn-ryr+… + Cnnyn)=1+ C1 nyx + C2ny2x2 +… + Crnyrxr +… + Cnnynxn+ λC0nxnyn + …     

利用柯西不等式的变式简解竞赛题

柯西不等式是高中数学中重要的不等式之一,它有如下重要变式： 若xi,yi∈R＋（i=1,2,...n,n∈N^＊,n≥2）,则有x^21/y1＋x^22/y2＋...＋x^2n/yn≥（x1＋x2＋...＋xn）^2/y1＋y2＋...＋yn,当且仅当x1/y1=x^2/y2=...=xn/yn时等号成立．     

题库(三十一)

1.已知点B1(1,y1),B2(2,y2),…,Bn(n,yn),…(n∈N+)顺次为直线y=x/4+1/12的点,点A1(x1,0),A2(x2,0),…,An(xn,0),…(n∈N+)顺次为x轴上的点,其中x1=a(0相似文献   

渐进准非扩张算子的迭代序列的收敛性

本着眼于渐进准非扩张算子的具有误差的Ishikawa迭代序列：xn 1=(1-αn)xn αnT'yn un yn=(1-βn)xn βnT'xn vn(n∈N） （αnβn∈[0,1]),的收敛性的研究，获得了其收敛于不动点的一个充分必要条件。     

关于两类递推数列的极限

根据不动点的定义和存在性定理 ,证明了两类递推数列 {xn 1=f(xn) }与 { yn 1=[f( yn) yn] / 2 }的极限存在 ,并且给出了计算它们的极限的方法。     

确定性的和具有随机扰动的Logistic映射的性质

给出了广义的Logisitc映射和θ=2时,系统log(xn 1)-log(xn)=r(1-xn2),0相似文献   

数列极限证明中的辅助函数(三)

阐述了如何借助于辅助函数,利用单调有界原理,证明数列xn+1=f (xn),n∈N极限存在.     

数列极限证明中的辅助函数（三）

阐述了如何借助于辅助函数，利用单调有界原理，证明数列xn 1=f(xn),n∈N极限存在。     

一类递推数列中的平方数

设{x n}是满足递推关系x0=1,x1=a>1,xn+2=2a x n+1-xn的数列.本文给出了:a=5,9,169以及9 801时所有可使xn是平方数的正整数n.     

关于不定方程XnYnZn=(Xn+Yn)n+2

根据费马大定理，运用基础数论的方法，证明了不定方程X^nY^nZ^n=（X^n＋Y^n）^n＋2，（n≥3）没有正整数解。     

方程xn+yn=zn在费波纳奇矩阵上的解

Fibonacci矩阵是一种特殊的二阶矩陈,广义Fibonacci矩阵是m(m>2)阶的Fibonacci矩阵,在广义Fibonacci矩阵集合中,方程xn yn=zn,n∈N,没有解(n,x,y,z)。     

形如f(x)=ax~m+b/x~n+c的函数模型

讨论了函数f(x)=ax~m＋b/x~n＋c的最值问题,并举例说明其应用.     

方程xn+yn=zn在费波纳奇矩阵上的解

Fibonacci矩阵是一种特殊的二阶矩陈,广义Fibonacci矩阵是m(m>2)阶的Fibonacci矩阵,在广义Fibonacci矩阵集合中方程xn yn=zn,n∈N,没有解(n,x,y,z).     

Diophantine方程xn+yn=zφ(n)的本原解

设n是正整数,φ(n)是Euler函数.证明了方程xn yn=zφ(n)当且仅当n≤3时有正整数解(x,y,z)适合gcd(x,y)=1.     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

Western and Eastern culture differences in commercial field

The communication of people partially is the communication of cultures. Culture has a direct effect on international commercial activities in all aspects. Different conceptions about time, space, equality, law and the like, lead people to deal with things in different ways. So to know cultures of the counterpart is to facil-itate our enterprises so as to have a smooth and successful communication in commercial activity.     

不同的吃喝玩乐

一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/     

漏洞百出的教育

Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?     

只要努力,不要后悔

There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.