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1.
本文利用有向循环图D(n,S)的矩阵表示,讨论了D(n,S)的一些谱性质。证明了D(n,S)强连通等价于其基础图连通,以及D(n,S)的连通分支数=g·c·d.(n,s_1,s_2,…s_r)=特征值│S│的重数。  相似文献   

2.
本文得到以下结果:1) [Dn (0, 1, 1, …, 1,0, 1, 1, …, l)]2 = Dn (n-2, n-4,…, n-4, n-2, n -4, …, n-4). 2) [Dn (0,1,1,…,1, 0, 0,…, 0)]2 = Dn (0, 0,1, 2,…,(n-3)/2, (n-1)/2,(n-3)/2, …,2, 1) (n is odd). [Dn (0,1,1,…,1, 0, 0,…, 0)]2 = Dn (1, 0, 1, 2,…, n/2-1,n/2, n/2-1, …,3,2) (n is even). 3) Dn (a0, a1 …, an-1)* Dn (0, 1, 0, …, 0)= Dn (an-1, a0, a1 a2, …, an-2). 4) Dn (a0, a1; …, an-1) * Dn (0, 1, 1, …, 1) = Dn (p-a0, p-a1,p-a2, …, p -an-1) (p=a0 + a1 + a2 +… + an-1).  相似文献   

3.
设多项式f(x)~aoxn+a:xn一’+……+a。一:x+‘,炳=b+(j一l)d,d笋。,j任N。那么n+z阶范得蒙行列式(以下总假定n)2): l bn+1 b盖+-lb3嘴1场嘴lbl日‘ 一一 Db全b呈b牙…b盆+1Dj D一(b厂bi)(b厂bZ)……(b厂b卜i)(bi+1一b:)(b:+:一bj)·,·…(饥+i一bJ) D(j一l)!(n+l一j)!d。 D_,一丁丁甲不“L节厂‘ n IU一从而1嘛嘛︸嵘粼1 11饥嘴 2,盆山bb 1工门‘11bbao .D=八Ua…试一laob全 lb晋一1aob呈 1b犷,aob呈依次给第i(i一1,2,……n)行元素乘以a。卜。,全部加到第n+1行的对应元素上去bn+1b若+:按第n十1行-一一展开一一艺(一1)·‘;+j .f(bj)·…  相似文献   

4.
5.证明:若a.b,c是三.角形的三边,且25二a+b+e,则。I因为2(a十b+c夕黑D十C十一竺- a+C en~厂2、十~一一一-二一‘二‘耳—} a+D\3/8·n一’.厂二一~十二生一\a+l〕匕+Cn专1丫" 6.给定5个实数U。,明:总能找到5个实数V。足下列条件.U,,U:,U3,U;.121丁,V,,V:.V3,、厂‘i}街及+击〕脚 a竺粤{竺〕〔梦(a一卜b+c)听以「匀(l)得到 (1)U;一V:eN: (2)习(\厂、一\rj)“<4. o‘i相似文献   

5.
我们遇到的证明题 ,常常用文字及数学符号进行叙述 ,表现了数学严密的逻辑性 .但是下面这些问题的证明除了可以用严格的逻辑证明外 ,用图形证明也不失一种直观、有效的证明方法 .问题 1 证明 14 + ( 14 ) 2 + ( 14 ) 3 + ( 14 ) 4+…= 13.证法 1:如图 1示图 1       图 2证法 2 :如图 2示 :问题 2   12 + 2 3 + 33 +… +n3 =( 1+ 2 + 3+… +n) 2 .证法 1:如图 3示 :图 3       图 4说明 :4× 1× 12 + 4× 2 × 2 2 + 4× 3× 32 + 4×4× 4 2 + 4× 5× 52 ={2 × ( 1+ 2 + 3+ 4+ 5) }24 × ( 13 + 2 3 + 33 + 43 + 53 ) …  相似文献   

6.
在高中物理教材利用打点计时器求物体加速度的实验中,物体拖动纸带运动,打点计时器在纸带上打下一系列的点,通过测量这些点的分布可以求出物体的加速度,对这些数据的处理,教材上通常用的方法是“逐差法”。其原理是:如图所示是利用一条打好点的纸带。s4%Ds1=3a1T2,s5%Ds2=3a2T2,s6%Ds2=3a3T2。T为物体通过每段位移所用的时间。a=a1+a2+a33=(s6+s5+s4)-(s3+s2+s1)(3T)2。若用s′i代表各段真实值,±Δsi代表各段测量误差a=∑6i=4(s′i±Δsi)-∑3i=1(s′i±Δsi)(3T)2。为了简便起见,假定每次测量出现的误差绝对值都等于0O±Δs0O,因为+…  相似文献   

7.
冯泰 《当代电大》2004,(5):86-89
练习题1 单项选择题( 1)已知准确值x 与其有t位有效数字的近似值x=0 0a1a2 …an×10 s(a1≠0 )的绝对误差是:|x -x|≤(  ) A .0 5 ×10 s-1-t     B .0 5 ×10 s-t C .0 5×10 s+1-t     D .0 5×10 s+t( 2 )用列主元消去法解线性方程组 3x1-  x2 +4x3 = 1-  x1+2x2 - 9x3 = 0- 4x1- 3x2 + x3 =- 1,第1次消元,选择主元为(  )。 A .3          B .4 C .- 4  D .- 9( 3)已知n+1个互异节点(x0 ,y0 ) ,(x1,y1) ,…,(xn,yn)和过这些点的拉格朗日插值基函数lk(x) (k =0 ,1,2 ,…,n) ,且ω(x) =(x…  相似文献   

8.
本文得到一般n边形的Ceva定理: 定理1.设A_1A_2…A_n为一个平面内的n边形,O为平面内一点,且O与A_1,A_2,…,A_n中任两点不共线,若A_iO交A_jA_(j+l)(i=1,2,…,n;j≠i,i-I)于B_(ji),则 multiply from i=1 to n[(A_iB_(i.i-k)/B_(i.i-k) A_(i+1))·(A_iB_(i.i+1+k)/B_(i.i+1+k)A_(i+1))]=1, 约定:1.若l∥AB,则认为l与线段AB(或BA)的延长线相交于无穷远点S,且AS=SB,2.若i=mn+p,j=qn+t,m,q∈Z,p,t=1,2,…,n,则B_(ij)=B_(p.t),A_i=A_p。(下同)  相似文献   

9.
艺{(1月一2十二,十i)己玉留1一〔1十2+·’·+(云一1)j三}二(l子2+…+时2︸rJ。(”+1) 自然数的立方和求法很多.本文给出一利,新领巧妙的方法.’.‘拌与云有相同奇偶性.故 可令,孟二占+t.i=“一t则一香‘(‘+1),‘一合‘(‘一‘) 云3=fZ·i二(‘+t)(s一t)=52一tZ王‘(‘+l)1‘一r乏*(:一、)‘」L‘“(l+2十…十i户一LI十2十一卜(‘一l)」2巧求sum from i=1 to n j_3@曹思江$湖南新化三中!417600~~  相似文献   

10.
例题show:(2006年高考·全国卷Ⅰ,22题).设数列{an}的前n项的和Sn=4/3an-1/3×2n+1+2/3,n=1,2,3,…。(Ⅰ)求首项a1与通项an;(Ⅱ)设Tn=2n/Sn,n=1,2,3,…,证明:(∑|i=1|n)Ti<3/2。命题指向:本题综合考查数列的概念及数列求和。(1)[基本思路]由Sn=4/3an-1/3×2n+1+2/3,n=1,2,3,…①。得a1=S1=4/3a1-1/3×4+2/3所以a1=2。再由①有Sn-1= 4/3an-1-1/3×2n+2/3,n=2,3,4,…②。将①和②相减得:an=Sn-  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.
《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   

13.
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   

14.
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   

15.
16.
1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec…  相似文献   

17.
Today, Sunday morning, I sit thinking and typing at my computer. My thoughts are in my homeland, India and my body is in China. The body is here and mind there for a good reason. Mr. Hu is president and I am resident and both are in each other's countries (what a difference the absence of one small letter makes!). Mr. Hu will return in a few days and I will stay on longer.  相似文献   

18.
STORIES     
正A One day a pig went to the stable(马棚)to see his good friend,an oldhorse,and was going to stay there forthenight.Night came and it was time forsleep.The pig went into the straw heap(稻草堆)and lay comfortably.A longtime passed,but the horse was stillstanding there and did not move.Thepig asked the horse why he did not go tosleep."Standing like this is the begin-ning ofsleeping,"answered the horse.  相似文献   

19.
正1.Any fool can count the seeds in an apple.Only God can count all the apples in one seed.2.Happy families are all alike;every unhappy family is unhappy in its own way.3.Memories are the key not to the past,but to the future.4.Sometimes in the dark you see what you want to see.5.There is a great difference between  相似文献   

20.
正Scope and Policy The Journal of Chongqing University-English Edition(JCQU-E)is a peerreviewed journal publishing research articles in multiple disciplines of science and technology,covering civil and environmental engineering,chemical engineering,biotechnology,mechanical and electrical engineering,computer and data processing,mining,metallurgy,materials science,and interdisciplines thereof.  相似文献   

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