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1.
对Hardy-Hilbert不等式进行了研究,并将其进一步改进如下:若p〉1,1/p+1/q=1,0〈A,B≤1,an,bn≥0,使0〈∑∞n=0apn〈∞,0〈∑∞n=0bqn〈∞,则∑∞m=0∑∞n=0ambn/Am+Bn+1〈{∑∞n=0(π/Bsin(π/p)-(3p-B)( p-1)/6p(2An+)11/p)anp}1/p{∑∞n=0(π/Asin(π/p)-(3q-A)(q-1)/6q(2Bn+1)1/q)bnq}1/q.所得结果改进和推广了最近文献的一些相应结果.  相似文献   

2.
利用傅里叶级数,得出3个递推公式,解决了p级数∑∞n=11/np与交错级数∑∞n=1(-1)n+1/np ,当p=2k时的收敛值问题.  相似文献   

3.
安徽省高中数学竞赛初赛的第15题是:已知数列{an}(n≥0)满足a0=0,对于所有非负整数n,有an+1=230an(an+1)+11an+5.求an的通项公式.参考答案是通过移项两边平方变形化简,最后求3次方程的特征根得到通项.下面给出两种较为简便的解法.解法1显然an+1>an≥0,n∈N,an+1=230an(an+1)+11an+5=5(an+1)+230an(an+1)+6an=(5(an+1)+6an)2,∴an+1=5(an+1)+6an,即an+1-6an=5(an+1),两边平方,化简得:an+1+an-26an+1an=5,n以n+1代替得:an+2+an+1-26an+2an+1=5,以上两式相减得:an+2-an-26an+1(an+2-an)=0;∵an+2>an+1>an,∴an+2+an-26an+1=0.令bn=an,则bn+2-2…  相似文献   

4.
<正>2008年高考数学浙江卷理科第22题:已知数列{an}:an≥0,a1=0,a2n+1+an+1-1=a2n(n∈N*).记Sn=a1+a2+…+an,  相似文献   

5.
试题已知a1=2,点(an,an+1)在函数f(x)=x2+2x的图象上,其中n=1,2,3…(Ⅰ)证明数列{lg(1+an)}是等比数列;(Ⅱ)设Tn=(1+a1)(1+a2)…(1+an),求Tn及数列{an}的通项;(Ⅲ)记bn=a1n+an1+2,求数列{bn}的前n项和Sn,并证明Sn+3Tn2-1=1.解(Ⅰ)由a1=2,且点(an,an+1)在f(x)=x2+2x的图象上,所以an+1=a2n+2an>0(n=1,2,3,…)所以llgg((11++aan+n)1)=lg(1lg+(12+ana+n)a2n)=2,所以数列{lg(1+an)}是以2为公比的等比数列.(Ⅱ)由(Ⅰ)知数列{lg(1+an)}的公比为2,第1项为lg3,从而lg(1+an)=2n-1lg3=lg32n-1,即1+an=32n-1(1)因此数列{an}的通项为an=32n-1-1.由(1)得…  相似文献   

6.
根据正项级数∑∞n=1un的敛散性,判别∑∞n=1un^k的敛散性的几个重要结论。  相似文献   

7.
等比数列求和公式为Sn=a1(11--qq n)(q≠1),有时用此公式证明不等式可简化证明过程.将数列知识与不等式知识相融合,既可培养学生思维的灵活性和创造性,又可简化思路、优化解题过程.一、直接公式法例1求证:1+21!+31!+41!+…+n1!<2(n≥2,n缀N).证明1+12!+31!+41!+…+n1!<1+12+212+123+…+21n-1=1×(11--121n)2=2-12n-1<2(n≥2,n缀N).故原不等式成立.小结本题直接运用等比数列求和公式,起到了立竿见影的效果.二、求和公式的逆用例2已知等差数列{an}和等比数列{bn}中a1=b1=a,a2=b2=b(b>a>0).求证:当n>2且n缀N时,bn>an.证明an=a+(n-1)(b-a)…  相似文献   

8.
指出数学分析中两个重要式子1imn→∞[1+1^n/n]=e与∑∞n=0n1/n!=e的等价关系并予以证明。  相似文献   

9.
数学归纳法主要用来证明一个与正整数有关的命题,它的步骤如下:1.证明当n取第一个值n0时结论正确;2.假设当n=k(k!N*,且k≥n0)时结论正确,证明当n=k 1时结论也正确.在完成了这两个步骤以后,就可以断定命题对于从n0开始的所有正整数n都正确.例1已知在各项均为正数的数列{an}中,它的前n项和Sn满足Sn=12(an a1n).试猜想数列{an}的通项公式,并用数学归纳法证明你的猜想.解析∵S1=a1=12(a1 a11),∴a21=1.∵an>0,∴a1=1.∵S2=a1 a2=12(a2 a12),即a22 2a2-1=0,又an>0,∴a2="2-1.∵S3=a1 a2 a3=1 ("2-1) a3=21(a3 a13),即a32 2"2a3-1=0,又an>0…  相似文献   

10.
此文研究单叶函数的Goluzin问题,拓广了胡克教授中关于单叶函数相邻系数的一个重要定理。当fk(z)=z ∑∞n=1n 1an 1^(k)z^kn 1∈Sc(α)时,得到‖an 1^(k)|—|an^(k)‖的准确估计。  相似文献   

11.
《海外英语》2007,(5):44-45
It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,  相似文献   

12.
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/  相似文献   

13.
《海外英语》2007,(5):10-11
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?  相似文献   

14.
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.  相似文献   

15.
《海外英语》2007,(4):36
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.  相似文献   

16.
王菲 《华章》2007,(12):273-273
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.  相似文献   

17.
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.  相似文献   

18.
Given a graph G,a subgraph C is called a clique of G if C is a complete subgraph of G maximal under inclusion and |C|≥2. A clique-transversal set S of G is a set of vertices of G such that S meets all cliques of G. The clique-transversal number, denoted as TC (G), is the minimum cardinality of a clique-transversal set in G. The clique-graph of G, denoted as K (G), is the graph obtained by taking the cliques of G as vertices, and two vertices are adjacent if and only if the corresponding cliques in G have nonempty intersection. Let F be a class of graphs G such that F={G|K(G) is a tree}. In this paper the graphs in F having independent clique-transversal sets are shown and thus TC (G)/|G|≤1/2 for all G ∈ F.  相似文献   

19.
裴水妹 《华章》2007,(11):196
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.  相似文献   

20.
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