有限簇非扩张映象具误差的黏性逼近

设E是一致光滑的Banach空间,C是E之一非空闭凸子集.设f∶C→C是一压缩映象,T1,T2…,TN∶C→C是一有限簇非扩张映象且∩iN=1F(Ti)≠θ.设序列{xn}定义为xn 1=αnf(xn) (1-αn-γn)Tnxn γnun.本文用黏性逼近方法证明了,在一定条件下,序列{xn}强收敛于T1,T2…,TN的一公共不动点.本文结果也推广和改进了最近一些人的最新结果.     

一类正整数次递归方程的解公式

获得了一类由x1及k(k∈N)次递归方程xn=akxn+1k+ak-1xn+1k-1+…+a1xn+1+a0(ak≠0)确定的递归数列{xn}的通项公式.所得的结果包含了许多已知的结论.     

数列不等式的证明方法

数列和不等式都是中学数学中非常重要的内容,也是高考的热点.近年来对数列和不等式的综合考查常被设置为高考压轴题,因为数列不等式的证明问题既要考虑不等式的证明方法,又要结合数列的特点,故综合性强,难度大.本文借助几道典型的高考试题,介绍数列不等式的常用证明方法.一、平均值不等式法例1已知数列{xn}由下列条件确定:x1=a>0,xn 1=21xn xan,n∈N*.证明:对任意的n∈N*且n≥2,总有xn≥a.证明由x1=a>0及xn 1=21xn xan,可归纳得xn>0.从而有xn 1=21xn xan≥xn.xan=a(n∈N*),所以当n≥2时,xn≥a成立.点评由于xn xan是“和”的形式,且xn、xan…     

求极限的技巧(高二)

求极限是高中数学的重点之一,本文以三例介绍三种求极限的特殊方法. 例1 设数列{xn}的x1=2,xn·1=(3X0+1)/(X0+3)·y0=(x0-1)/(xn+1),求limxn. 分析乍一看此题,觉得给出的y0=(x0-1)/(x0+1)的条件似乎多余,但本题可通过y,间接求xn的极限.     

有限簇L—Lipschitzian映象的迭代程序

设E是一实Banach空间,K是E的一非空闭凸子集.设f:K→K是一压缩映象,T1,T2,…,Tn:K→K是具序列{kn}(c)[1,+∞),lim n→∞ kn=1的有限簇一致L-Lipschitzian渐近伪压缩映象,且∩N/(i=1)F(Ti)≠φ.设序列{xn}定义为xn+1=(1-αn-βn)xn+αnf(xn)+βnTrn/nxn,其中{αn},{βn} (c)[O,1],rn=n mod N是值域为{ 1,2,…,N}的模函数.在一定条件证明了迭代序列{xn}强收敛于T1,T2,…,Tn的公共不动点.推广和改进了张石生等人的最新结果.     

差分方程χn+1=1/(χn+χn-1)的动力学分析

采用半环分析法研究差分方程xn+1=1/(xn+xn-1)(n=0,1,…)解列{xn}n∞=-1 的特性.在此基础上,给出在初始值满足x-1,x0∈(0,∞)情况下,其平衡点(x-)=(∫2/2)是全局渐近稳定的严格理论证明.     

谈2012年全国卷(理二)第22题的解答

题目(2012年全国卷(二)第22题):函数f(x)=x2-2x-3,定义数列{xn}如下:x1=2,xn+1是过两点P(4,5),Qn(xn,f(xn))的直线PQn与x轴交点的横坐标.(Ⅰ)证明:2≤xn相似文献   

一个不等式猜想及证明

猜想(数学问题315.2) 议xi>0,i=1,2,…,n(n≥3),则有Sn=x2/x1(x3 x4 … xn) x3/x2(x4 … xn x1) … xn/xn-1(x1 x2 … xn-2) x1/xn(x2 x3 … xn-1)≥(n-2)n∑i=1xi.     

高等数学背景下的高考命题探究——2012年全国数学高考理科卷第22题

题目设函数f(x)=x2-2x-3,定义数列{xn}如下:x1=2,xn+1是过点P(4,5),Qn(xn,f(xn))的直线PQn与x轴交点的横坐标.(1)证明:2≤xn相似文献   

一个带参数的分式不等式及其应用

定理设xi>0,(i=1,2,…,n),若k≥1,则x1/kx1 x2 x3 … xn x2/x1 kx2 x3 … xn … xn/x1 x2 x3 … kxn≤n/n k-1.(1)若k<1,则不等式(1)不等号反向.证明因为不等式左端是关于x1,x2,…,xn的一次齐次对称式,故可设x1 x2 x3 … xn=1,则不等式(1)可以分为     

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,     

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?     

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.     

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.     

浅谈移民问题

Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.     

Sister Carrie, an Adherent of Desires

Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.     

Improvement of one-cycle controller by use of proportional integral differential controller

1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec…     

风的曲线

Rosco and I wait for the fishermen to return.I sit at a wooden bench near the store at Mt.Baker Resort and watch the clouds change shape. Rosco has my belt around his neck and an eight foot tow chain hooked to a tree. Dogs must be on a leash. Ducks and rabbits are loose.