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排序方式: 共有310条查询结果,搜索用时 140 毫秒
31.
We present a new third order method for finding multiple roots of nonlinear equations based on the scheme for simple roots developed by Kou et al. [J. Kou, Y. Li, X. Wang, A family of fourth-order methods for solving non-linear equations, Appl. Math. Comput. 188 (2007) 1031-1036]. Further investigation gives rise to new third and fourth order families of methods which do not require second derivative. The fourth order family has optimal order, since it requires three evaluations per step, namely one evaluation of function and two evaluations of first derivative. The efficacy is tested on a number of relevant numerical problems. Computational results ascertain that the present methods are competitive with other similar robust methods. 相似文献
32.
对一个图G,设μ(G,x)表示它的匹配多项式,M(G,x)表示μ(G,x)的最大实数根.令Г_1={G|M(G,x)<2}和Г2={G|M(G,x)≤2}.给出了Г_i(i=1,2)中的两个图G和H匹配等价的充要条件. 相似文献
33.
杨合俊 《数学的实践与认识》2011,41(1)
研究秦九韶"正负开方术"的收敛速度.采用分析算法的几何意义、使用这一算法求解具体的高次方程以及数学证明的方法.发现秦九韶法与牛顿切线法类似.秦九韶正负开方术是二阶收敛的. 相似文献
34.
This study explores the grasp of square roots among eleven students in a remedial mathematics course, with a special focus on where the same student generated apparently conflicting responses. Building on the commognitive framework, the analysis distinguished between routines that individual students consistently implemented in situations where roots “stood alone” and where they were incorporated in more compound exercises, where roots were extracted from square numbers and from squared radicands, where roots were applied to monomials and binomials, and where parameters named with different letters were involved. Differences were found in routines’ degree of objectification, procedures, and tasks. These differences are explained with a theoretical account, suggesting that what may seem as a conflict within a student’s discourse could be a sensible difference of actions taken in situations that this student construed as different. The contribution of this study to the body of knowledge on teaching and learning of roots and to commognitive research is discussed. 相似文献
35.
Fernando Rodriguez-Villegas 《Proceedings of the American Mathematical Society》2002,130(8):2251-2254
We prove that certain naturally arising polynomials have all of their roots on a vertical line. 相似文献
36.
Arturas Dubickas 《Siberian Mathematical Journal》2006,47(5):879-882
Let ξ ≠ = 0 and α > 1 be reals. We prove that the fractional parts {ξ αn}, n = 1, 2, 3, ..., take every value only finitely many times except for the case when α is the root of an integer: α = q 1/d, where q ≥ 2 and d ≥ 1 are integers and ξ is a rational factor of a nonnegative integer power of α. 相似文献
37.
We obtain sufficient conditions for the set of roots of an entire function of order zero of strongly regular growth to possess an angular density. 相似文献
38.
Viktor Ostrik 《Compositio Mathematica》2002,132(3):283-287
Let U be a quantumgroup with divid d powers at root ofunity constructed froma rootsystem R .Let u U b th small quantumgroup.Th cohomologyof u with trivial coefficients was computed by Ginzburg and Kumar.It turns out to be isomorphic to the functions algebra of the nilpotent cone of a semisimpl algebraic group with root system R .In this not we calculate cohomology of u with coefficients in simplest reducible tilting modul with nontrivial cohomology.It appears to b isomorphic to th functions algebra of th closure of the subregular nilpotent orbit. 相似文献
39.
Y. Fujikoshi 《Journal of multivariate analysis》1977,7(3):386-396
Asymptotic expansions are given for the density function of the normalized latent roots of S1S2?1 for large n under the assumption of , where S1 and S2 are independent noncentral and central Wishart matrices having the and Wp(n, Σ) distributions, respectively. The expansions are obtained by using a perturbation method. Asymptotic expansions are also obtained for the density function of the normalized canonical correlations when some of the population canonical correlations are zero. 相似文献
40.
C.S. Jog 《Journal of Elasticity》2002,66(2):159-169
A method for the explicit determination of the polar decomposition (and the related problem of finding tensor square roots) when the underlying vector space dimension n is arbitrary (but finite), is proposed. The method uses the spectral resolution, and avoids the determination of eigenvectors when the tensor is invertible. For any given dimension n, an appropriately constructed van der Monde matrix is shown to play a key role in the construction of each of the component matrices (and their inverses) in the polar decomposition. 相似文献