Some Inequalities Concerning the Polar Derivative of a Polynomial-II

In this paper, we consider the class of polynomials P（z）= anz^n＋ ∑vn=μan-vz^n-v,1≤μ≤n , having all zeros in ｜z｜≤k, k ≤1 and thereby present an alternative proof, independent of Laguerre＇s theorem, of an inequality concerning the polar derivative of a polynomial.

Inequalities for the Polar Derivatives of a Polynomial

Let P（z） be a polynomial of degree n, having all its zeros in ｜z｜≤ 1. In this paper, we estimate kth polar derivative of P（z） on ｜z｜ = 1 and thereby obtain compact generalizations of some known results which among other things yields a refinement of a result due to Paul Tura＇n.

ON EXTREMAL PROPERTIES FOR THE POLAR DERIVATIVE OF POLYNOMIALS

If p（z） is a polynomial of degree n having all its zeros on ｜z｜ = k, k ≤ 1, then it is proved[5] that In this paper, we generalize the above inequality by extending it to the polar derivative of a polynomial of the type We also obtain certain new inequalities concerning the maximum modulus of a polynomial with restricted zeros.

SOME INTEGRAL INEQUALITIES FOR THE POLAR DERIVATIVE OF A POLYNOMIAL

If P（z） is a polynomial of degree n which does not vanish in ｜z｜ 〈 1, then it is recently proved by Rather [Jour. Ineq. Pure andAppl. Math., 9 （2008）, Issue 4, Art. 103] that for every γ 〉 0 and every real or complex number a with ｜ α ｜ ≥ 1,{∫ 2π 0｜DαP（e^iθ）｜γdθ｜}^1/γ≤n（｜α｜＋1）Cγ{∫2π0｜P（e^iθ）｜γ^dθ}^1/γ,Cγ={1/2π∫2π 0｜1＋e^iβ｜^γdβ}^-1/γ,where DaP（z） denotes the polar derivative of P（z） with respect to α. In this paper we prove a result which not only provides a refinement of the above inequality but also gives a result of Aziz and Dawood [J. Approx. Theory, 54 （1988）, 306-313] as a special case.

Some Results on the Polar Derivative of a Polynomial

Let P（z） be a polynomial of degree n and for any complex number α, let DαP（z） = nP（z）＋ （α-z）P＇ （z） denote the polar derivative of P（z） with respect to α. In this paper, we obtain certain inequalities for the polar derivative of a polynomial with restricted zeros. Our results generalize and sharpen some well-known polynomial inequalities.

Some Lγ Inequalities for the Polar Derivative of a Polynomial

In this paper, we consider an operator Da which maps a polynomial P（z） in to DaP（z）：= np（z）＋ （a-z）P＇（z）, where and obtain some Lγ inequalities for lucanary polynomials having zeros in /z/ 〈 k 〈 1. Our results yields several generaliza- tions and refinements of many known results and also provide an alternative proof of a result due to Dewan et al. [7], which is independent of Laguerre＇s theorem.

Some Inequalities on Polar Derivative of Polynomial Having No Zero in a Disc

Let , , be a polynomial of degree n having no zero in , , then Qazi [Proc. Amer. Math. Soc., 115 (1992), 337-343] proved . In this paper, we first extend the above inequality to polar derivative of a polynomial. Further, as an application of our result, we extend a result due to Dewan et al. [Southeast Asian Bull. Math., 27 (2003), 591-597] to polar derivative.

Polar Derivative Versions of Polynomial Inequalities

Let be a polynomial of degree n and for a complex number , let ?denote the polar derivative of the polynomial ?with respect to . In this paper, first we extend as well as generalize the result proved by Dewan and Mir [Inter. Jour. Math. and Math. Sci., 16 (2005), 2641-2645] to polar derivative. Besides, another result due to Dewan et al. [J. Math. Anal. Appl. 269 (2002), 489-499] is also extended to polar derivative.

Inequalities for the Polar Derivative of a Polynomial

If is a polynomial of degree , having all its zeros in |z|≤K, K≥1 , then it was proved by Aziz and Rather [2] that for every real or complex number with |a| ≥K, . In this paper, we sharpen above result for the polynomials p(z) of degree n>

ON APPROXIMATION OF A FUNCTION AND ITS DERIVATIVES BY A POLYNOMIAL AND ITS DERIVATIVES

Let g∈C^q[-1, 1] be such that g^((k))(±1)=0 for k=0,…,q. Let P_n be an algebraic polynomial of degree at most n, such that P_n^((k))(±1)=0 for k=0,…,[_2~ (q+1)]. Then P_n and its derivatives P_n^((k)) for k≤q well approximate g and its respective derivatives, provided only that P_n well approxi- mates g itself in the weighted norm ‖g(x)-P_n(x) (1-x^2)^(1/2)~q‖ This result is easily extended to an arbitrary f∈C^q[-1, 1], by subtracting from f the polynomial of minnimal degree which interpolates f^((0))…,f^((q)) at±1. As well as providing easy criteria for judging the simultaneous approximation properties of a given Polynomial to a given function, our results further explain the similarities and differences between algebraic polynomial approximation in C^q[-1, 1] and trigonometric polynomial approximation in the space of q times differentiable 2π-periodic functions. Our proofs are elementary and basic in character, permitting the construction of actual error estimates for simultaneous approximation proedures for small values of q.

Study of Fractional Order Dynamical System of Viral Infection Disease under Piecewise Derivative

This research aims to understand the fractional order dynamics of the deadly Nipah virus(NiV)disease.We focus on using piecewise derivatives in the context of classical and singular kernels of power operators in the Caputo sense to investigate the crossover behavior of the considered dynamical system.We establish some qualitative results about the existence and uniqueness of the solution to the proposed problem.By utilizing the Newtonian polynomials interpolation technique,we recall a powerful algorithm to interpret the numerical findings for the aforesaid model.Here,we remark that the said viral infection is caused by an RNA type virus which can transmit from animals and also from an infected person to person.Fruits bats which are also known as flying foxes are one of the sources of transmission of NiV disease.Here in this work,we investigate its transmission mechanism through some new concepts of fractional calculus for further analysis and prediction.We present the approximate results for different compartments using different fractional orders.By using the piecewise derivative concept,we detect the crossover ormulti-steps behavior in the transmission dynamics of the mentioned disease.Therefore,the considered form of the derivative is used to deal with problems exhibiting crossover behaviors.

A Kind of Identities Involving Complete Bell Polynomials

The purpose of this paper is to establish a formula of higher derivative by Faà di Bruno formula, and apply it to some known results to get some identities involving complete Bell polynomials.

Oxidation of chalcopyrite in air-equilibrated acidic solution: Inhibition with phenacyl derivatives

The effects of 4-(2-hydroxyphenyl)-2-(morpholin-4-yl)-1,3-thiazole(Pr02), 1-(3,5-dibromo-2-hydroxyphenyl)-1-oxoethan-2-yl-N,N-diethyldithiocarbamate(Pr04) and 1-(5-bromo-2-hydroxy-3-methylphenyl)-1-oxoethan-2-yl-Oethyl xanthate(Pr06) on the aqueous oxidation of chalcopyrite(CuFeS2) in air-equilibrated solution at a temperature of 25 ℃ and a pH of 2.5 were studied. The effects were investigated by using potentiodynamic polarization, electrochemical impedance spectroscopy(EIS), scanning electron microscopy coupled with energy dispersive X-ray(SEM/EDX) analysis, aqueous batch experiments, Fourier transform infrared(FTIR) spectroscopy, Raman scattering and quantum chemical calculations. It is found that the anodic current densities decrease in the order of EtOH > Pr02 > Pr04 > Pr06. These results, along with those of the EIS measurements, show that Pr02, Pr04 and Pr06 are effective anodic inhibitors of chalcopyrite aqueous oxidation. Both Raman scattering and FTIR spectroscopy indicate that the elemental sulfur, polysulfide and ferric oxyhydroxides that form on the surface of the mineral are not responsible when it comes to the aqueous oxidation inhibition of chalcopyrite. Quantum chemical calculations show that the adsorption of the tested compounds on the chalcopyrite surface is energetically favorable and so, it can explain the inhibiting effects that were observed.

Theoretical derivation and simulation of a versatile electrostatic trap for cold polar molecules

We propose a versatile electrostatic trap scheme using several charged spherical electrodes and a bias electric held.We hrst give the two-ball scheme and derive the analytical solution of the electric held.In order to make a comparison,we also give the numerical solution calculated by the hnite element software（Ansoft Maxwell）.Considering the loading of cold polar molecules into the trap,we give the three-ball scheme.We hrst give the analytical and numerical solutions of the distribution of the electric held.Then we simulate the dynamic process of the loading and trapping cold molecules using the classical Monte Carlo method.We analyze the influence of the velocity of the incident molecular beam and the loading time on the loading efficiency.After that,we give the temperature of the trapped cold molecules.Our study shows that the loading efficiency can reach 82%,and the corresponding temperature of the trapped molecules is about 24.6 mK.At last,we show that the single well divides into two ones by increasing the bias electric held or decreasing the voltages applied to the spherical electrodes.

SIMULTANEOUSE APPROXIMATION TO A DIFFERENTIABLE FUNCTION AND ITS DERIVATIVES BY LAGRANGE INTERPOLATING POLYNOMIALS

This paper establishes the following pointwise result for simultancous Lagrange imterpolating approxima- tion:,then |f^(k)(x)-P_n^(k)(f,x)|=O(1)△_n^(q-k)(x)ω where P_n(f,x)is the Lagrange interpolating potynomial of deereeon the nodes X_nUY_n(see the definition of the next).

On an Inequality of Pual Turan Concerning Polynomials-Ⅱ

Let P（z） be a polynomial of degree n and for any complex number α, let D;P（z） = nP（z）+（α- z） P′（z） denote the polar derivative of the polynomial P（z） with respect to α. In this paper, we obtain inequalities for the polar derivative of a polynomial having all zeros inside a circle. Our results shall generalize and sharpen some well-known results of Turan, Govil, Dewan et al. and others.

Maximum Modulus of Polynomials

The result is best possible. In this paper we shall present a refinement of this result and some other related results.

A CLASS OF INEQUALITIES ABOUT BERNSTEIN POLYNOMIAL AND THEIR APPLICATIONS

In this paper a class of new inequalities about Bernstein polynomial is established. With these inequalities, the estimation of heights, the derivative bounds of Bézier curves and rational Bézier curves can be improved greatly.

On the Approximate Solution of Fractional Logistic Differential Equation Using Operational Matrices of Bernstein Polynomials

In this paper, operational matrices of Bernstein polynomials (BPs) are presented for solving the non-linear fractional Logistic differential equation (FLDE). The fractional derivative is described in the Riemann-Liouville sense. The operational matrices for the fractional integration in the Riemann-Liouville sense and the product are used to reduce FLDE to the solution of non-linear system of algebraic equations using Newton iteration method. Numerical results are introduced to satisfy the accuracy and the applicability of the proposed method.

CONVERGENCE OF DERIVATIVES OF GENERALIZED BERNSTEIN OPERATORS

In the present paper, we obtain estimations of convergence rate derivatives of the q-Bernstein polynomials Bn （f, qn ;x） approximating to f＇ （x） as n →∞, which is a general- ization of that relating the classical case qn = 1. On the other hand, we study the conver- gence properties of derivatives of the limit q-Bernstein operators B∞（f, q;x） as q→1-.