The Experts below are selected from a list of 1047 Experts worldwide ranked by ideXlab platform

Yuming Chu - One of the best experts on this subject based on the ideXlab platform.

  • approximations for the Complete Elliptic Integral of the second hbox kind kind
    Revista De La Real Academia De Ciencias Exactas Fisicas Y Naturales Serie A-matematicas, 2021
    Co-Authors: Weimao Qian, Miao-kun Wang, Yuming Chu
    Abstract:

    In this paper, we present the best possible parameters $$\alpha _{1}$$ , $$\alpha _{2}$$ , $$\alpha _{3}$$ , $$\alpha _{4}$$ , $$\beta _{1}$$ , $$\beta _{2}$$ , $$\beta _{3}$$ , $$\beta _{4} \in {\mathbb {R}}$$ such that $$\begin{aligned} \frac{\alpha _{1}}{H(x, y)}+\frac{1-\alpha _{1}}{L(x, y)}&<\frac{1}{V(x, y)}<\frac{\beta _{1}}{H(x, y)}+\frac{1-\beta _{1}}{L(x, y)},\\ \frac{\alpha _{2}}{H(x, y)}+\frac{1-\alpha _{2}}{P(x, y)}&<\frac{1}{V(x, y)}<\frac{\beta _{2}}{H(x, y)}+\frac{1-\beta _{2}}{P(x, y)},\\ \frac{\alpha _{3}}{H(x, y)}+\frac{1-\alpha _{3}}{N S(x, y)}&<\frac{1}{V(x, y)}<\frac{\beta _{3}}{H(x, y)}+\frac{1-\beta _{3}}{N S(x, y)},\\ \frac{\alpha _{4}}{H(x, y)}+\frac{1-\alpha _{4}}{T(x, y)}&<\frac{1}{V(x, y)}<\frac{\beta _{4}}{H(x, y)}+\frac{1-\beta _{4}}{T(x, y)} \end{aligned}$$ hold for all $$x, y>0$$ with $$x \ne y$$ , where H(x, y), G(x, y), L(x, y), A(x, y), NS(x, y), P(x, y) and T(x, y) are respectively the harmonic, geometric, logarithmic, arithmetic, Neuman-Sandor, and first and second Seiffert means of two distinct positive numbers x and y, and $$\begin{aligned} V(x,y)=\pi G^{2}(x, y) /\left[ 2\int _{0}^{\pi /2}\sqrt{A^{2}(x,y) \cos ^{2}\varphi +G^{2}(x,y)\sin ^{2}\varphi }d\varphi \right] \end{aligned}$$ is a new Seiffert-like mean. As applications, some new inequalities for the Complete Elliptic Integral of the second kind are given.

  • a sharp double inequality involving generalized Complete Elliptic Integral of the first kind
    Math 2020 Vol. 5 Pages 4512-4528, 2020
    Co-Authors: Tiehong Zhao, Miao-kun Wang, Yuming Chu
    Abstract:

    In the article, we establish a sharp double inequality involving the ratio of generalized Complete Elliptic Integrals of the first kind, which is the improvement and generalization of some previously known results.

  • approximation for the Complete Elliptic Integral of the first kind
    Revista De La Real Academia De Ciencias Exactas Fisicas Y Naturales Serie A-matematicas, 2020
    Co-Authors: Weimao Qian, Yuming Chu
    Abstract:

    In the article, we present several sharp upper and lower bounds for the Complete Elliptic Integral of the first kind in terms of inverse trigonometric and inverse hyperbolic functions. As consequences, some sharp bounds for the Gaussian arithmetic-geometric mean in terms of other bivariate means are also given.

  • high accuracy asymptotic bounds for the Complete Elliptic Integral of the second kind
    Applied Mathematics and Computation, 2019
    Co-Authors: Yuming Chu, Zhenhang Yang, Wen Zhang
    Abstract:

    Abstract In the article, we prove that the double inequality π 2 J ( r ′ ) − 51 π − 160 160 r 16 E ( r ) π 2 J ( r ′ ) − 5 π 3 × 2 31 r 16 holds for all r ∈ (0, 1), where E ( r ) = ∫ 0 π / 2 1 − r 2 sin 2 ( t ) d t is the Complete Elliptic Integral of the second kind, r ′ = ( 1 − r 2 ) 1 / 2 and J ( r ) = 51 r 2 + 20 r r + 50 r + 20 r + 51 16 ( 5 r + 2 r + 5 ) .

  • monotonicity rule for the quotient of two functions and its application
    Journal of Inequalities and Applications, 2017
    Co-Authors: Zhenhang Yang, Weimao Qian, Yuming Chu, Wen Zhang
    Abstract:

    In the article, we provide a monotonicity rule for the function $[P(x)+A(x)]/[P(x)+B(x)]$ , where $P(x)$ is a positive differentiable and decreasing function defined on $(-R, R)$ ( $R>0$ ), and $A(x)=\sum ^{\infty}_{n=n_{0}}a_{n}x^{n}$ and $B(x)=\sum^{\infty }_{n=n_{0}}b_{n}x^{n}$ are two real power series converging on $(-R, R)$ such that the sequence $\{a_{n}/b_{n}\}_{n=n_{0}}^{\infty}$ is increasing (decreasing) with $a_{n_{0}}/b_{n_{0}}\geq(\leq)\ 1$ and $b_{n}>0$ for all $n\geq n_{0}$ . As applications, we present new bounds for the Complete Elliptic Integral $\mathcal{E}(r)=\int_{0}^{\pi /2}\sqrt{1-r^{2}\sin^{2}t}\,dt$ ( $0< r<1$ ) of the second kind.

Miao-kun Wang - One of the best experts on this subject based on the ideXlab platform.

  • approximations for the Complete Elliptic Integral of the second hbox kind kind
    Revista De La Real Academia De Ciencias Exactas Fisicas Y Naturales Serie A-matematicas, 2021
    Co-Authors: Weimao Qian, Miao-kun Wang, Yuming Chu
    Abstract:

    In this paper, we present the best possible parameters $$\alpha _{1}$$ , $$\alpha _{2}$$ , $$\alpha _{3}$$ , $$\alpha _{4}$$ , $$\beta _{1}$$ , $$\beta _{2}$$ , $$\beta _{3}$$ , $$\beta _{4} \in {\mathbb {R}}$$ such that $$\begin{aligned} \frac{\alpha _{1}}{H(x, y)}+\frac{1-\alpha _{1}}{L(x, y)}&<\frac{1}{V(x, y)}<\frac{\beta _{1}}{H(x, y)}+\frac{1-\beta _{1}}{L(x, y)},\\ \frac{\alpha _{2}}{H(x, y)}+\frac{1-\alpha _{2}}{P(x, y)}&<\frac{1}{V(x, y)}<\frac{\beta _{2}}{H(x, y)}+\frac{1-\beta _{2}}{P(x, y)},\\ \frac{\alpha _{3}}{H(x, y)}+\frac{1-\alpha _{3}}{N S(x, y)}&<\frac{1}{V(x, y)}<\frac{\beta _{3}}{H(x, y)}+\frac{1-\beta _{3}}{N S(x, y)},\\ \frac{\alpha _{4}}{H(x, y)}+\frac{1-\alpha _{4}}{T(x, y)}&<\frac{1}{V(x, y)}<\frac{\beta _{4}}{H(x, y)}+\frac{1-\beta _{4}}{T(x, y)} \end{aligned}$$ hold for all $$x, y>0$$ with $$x \ne y$$ , where H(x, y), G(x, y), L(x, y), A(x, y), NS(x, y), P(x, y) and T(x, y) are respectively the harmonic, geometric, logarithmic, arithmetic, Neuman-Sandor, and first and second Seiffert means of two distinct positive numbers x and y, and $$\begin{aligned} V(x,y)=\pi G^{2}(x, y) /\left[ 2\int _{0}^{\pi /2}\sqrt{A^{2}(x,y) \cos ^{2}\varphi +G^{2}(x,y)\sin ^{2}\varphi }d\varphi \right] \end{aligned}$$ is a new Seiffert-like mean. As applications, some new inequalities for the Complete Elliptic Integral of the second kind are given.

  • a sharp double inequality involving generalized Complete Elliptic Integral of the first kind
    Math 2020 Vol. 5 Pages 4512-4528, 2020
    Co-Authors: Tiehong Zhao, Miao-kun Wang, Yuming Chu
    Abstract:

    In the article, we establish a sharp double inequality involving the ratio of generalized Complete Elliptic Integrals of the first kind, which is the improvement and generalization of some previously known results.

  • optimal combinations bounds of root square and arithmetic means for toader mean
    Proceedings - Mathematical Sciences, 2012
    Co-Authors: Miao-kun Wang
    Abstract:

    We find the greatest value α1 and α2, and the least values β1 and β2, such that the double inequalities α1S(a,b) + (1 − α1) A(a,b) 0 with a ≠ b. As applications, we get two new bounds for the Complete Elliptic Integral of the second kind in terms of elementary functions. Here, S(a,b) = [(a2 + b2)/2]1/2, A(a,b) = (a + b)/2, and \(T(a,b)=\frac{2}{\pi}\int\limits_{0}^{{\pi}/{2}}\sqrt{a^2{\cos^2{\theta}}+b^2{\sin^2{\theta}}}{\rm d}\theta\) denote the root-square, arithmetic, and Toader means of two positive numbers a and b, respectively.

  • On Alzer and Qiu's Conjecture for Complete Elliptic Integral and Inverse Hyperbolic Tangent Function
    Abstract and Applied Analysis, 2011
    Co-Authors: Miao-kun Wang
    Abstract:

    We prove that the double inequality (

Matti Vuorinen - One of the best experts on this subject based on the ideXlab platform.

Wen Zhang - One of the best experts on this subject based on the ideXlab platform.

  • high accuracy asymptotic bounds for the Complete Elliptic Integral of the second kind
    Applied Mathematics and Computation, 2019
    Co-Authors: Yuming Chu, Zhenhang Yang, Wen Zhang
    Abstract:

    Abstract In the article, we prove that the double inequality π 2 J ( r ′ ) − 51 π − 160 160 r 16 E ( r ) π 2 J ( r ′ ) − 5 π 3 × 2 31 r 16 holds for all r ∈ (0, 1), where E ( r ) = ∫ 0 π / 2 1 − r 2 sin 2 ( t ) d t is the Complete Elliptic Integral of the second kind, r ′ = ( 1 − r 2 ) 1 / 2 and J ( r ) = 51 r 2 + 20 r r + 50 r + 20 r + 51 16 ( 5 r + 2 r + 5 ) .

  • on approximating the arithmetic geometric mean and Complete Elliptic Integral of the first kind
    Journal of Mathematical Analysis and Applications, 2018
    Co-Authors: Zhenhang Yang, Weimao Qian, Wen Zhang
    Abstract:

    Abstract In the article, we prove that the double inequalities 1 + ( 6 p − 7 ) r ′ p + ( 5 p − 6 ) r ′ π tanh − 1 ⁡ ( r ) 2 r K ( r ) 1 + ( 6 q − 7 ) r ′ q + ( 5 q − 6 ) r ′ π tanh − 1 ⁡ ( r ) 2 r , q A ( 1 , r ) + ( 5 q − 6 ) G ( 1 , r ) A ( 1 , r ) + ( 6 q − 7 ) G ( 1 , r ) L ( 1 , r ) A G M ( 1 , r ) p A ( 1 , r ) + ( 5 p − 6 ) G ( 1 , r ) A ( 1 , r ) + ( 6 p − 7 ) G ( 1 , r ) L ( 1 , r ) hold for all r ∈ ( 0 , 1 ) if and only if p ≥ π / 2 = 1.570796 ⋯ and q ≤ 89 / 69 = 1.289855 ⋯ , where K ( r ) = ∫ 0 π / 2 ( 1 − r 2 sin 2 ⁡ t ) − 1 / 2 d t is the Complete Elliptic Integral of the first kind, tanh − 1 ⁡ ( r ) = log ⁡ [ ( 1 + r ) / ( 1 − r ) ] / 2 is the inverse hyperbolic tangent function, r ′ = 1 − r 2 , and A ( 1 , r ) = ( 1 + r ) / 2 , G ( 1 , r ) = r , L ( 1 , r ) = ( r − 1 ) / log ⁡ r and A G M ( 1 , r ) are the arithmetic, geometric, logarithmic and Gaussian arithmetic-geometric means of 1 and r , respectively.

  • monotonicity rule for the quotient of two functions and its application
    Journal of Inequalities and Applications, 2017
    Co-Authors: Zhenhang Yang, Weimao Qian, Yuming Chu, Wen Zhang
    Abstract:

    In the article, we provide a monotonicity rule for the function $[P(x)+A(x)]/[P(x)+B(x)]$ , where $P(x)$ is a positive differentiable and decreasing function defined on $(-R, R)$ ( $R>0$ ), and $A(x)=\sum ^{\infty}_{n=n_{0}}a_{n}x^{n}$ and $B(x)=\sum^{\infty }_{n=n_{0}}b_{n}x^{n}$ are two real power series converging on $(-R, R)$ such that the sequence $\{a_{n}/b_{n}\}_{n=n_{0}}^{\infty}$ is increasing (decreasing) with $a_{n_{0}}/b_{n_{0}}\geq(\leq)\ 1$ and $b_{n}>0$ for all $n\geq n_{0}$ . As applications, we present new bounds for the Complete Elliptic Integral $\mathcal{E}(r)=\int_{0}^{\pi /2}\sqrt{1-r^{2}\sin^{2}t}\,dt$ ( $0< r<1$ ) of the second kind.

  • monotonicity rule for the quotient of two functions and its application
    Journal of Inequalities and Applications, 2017
    Co-Authors: Zhenhang Yang, Weimao Qian, Wen Zhang
    Abstract:

    In the article, we provide a monotonicity rule for the function $[P(x)+A(x)]/[P(x)+B(x)]$ , where $P(x)$ is a positive differentiable and decreasing function defined on $(-R, R)$ ( $R>0$ ), and $A(x)=\sum ^{\infty}_{n=n_{0}}a_{n}x^{n}$ and $B(x)=\sum^{\infty }_{n=n_{0}}b_{n}x^{n}$ are two real power series converging on $(-R, R)$ such that the sequence $\{a_{n}/b_{n}\}_{n=n_{0}}^{\infty}$ is increasing (decreasing) with $a_{n_{0}}/b_{n_{0}}\geq(\leq)\ 1$ and $b_{n}>0$ for all $n\geq n_{0}$ . As applications, we present new bounds for the Complete Elliptic Integral $\mathcal{E}(r)=\int_{0}^{\pi /2}\sqrt{1-r^{2}\sin^{2}t}\,dt$ ( $0< r<1$ ) of the second kind.

  • optimal inequalities for bounding toader mean by arithmetic and quadratic means
    Journal of Inequalities and Applications, 2017
    Co-Authors: Tiehong Zhao, Wen Zhang
    Abstract:

    In this paper, we present the best possible parameters $\alpha(r)$ and $\beta(r)$ such that the double inequality $$\begin{aligned} \bigl[\alpha(r)A^{r}(a,b)+ \bigl(1-\alpha(r) \bigr)Q^{r}(a,b) \bigr]^{1/r} < & TD \bigl[A(a,b), Q(a,b) \bigr] \\ < & \bigl[\beta(r)A^{r}(a,b)+ \bigl(1-\beta(r) \bigr)Q^{r}(a,b) \bigr]^{1/r} \end{aligned}$$ holds for all $r\leq 1$ and $a, b>0$ with $a\neq b$ , and we provide new bounds for the Complete Elliptic Integral $\mathcal{E}(r)=\int_{0}^{\pi/2}(1-r^{2}\sin^{2}\theta)^{1/2}\,d\theta$ $(r\in (0, \sqrt{2}/2))$ of the second kind, where $TD(a,b)=\frac{2}{\pi}\int_{0}^{\pi/2}\sqrt{a^{2}\cos^{2}\theta+b^{2}\sin^{2}\theta}\,d\theta$ , $A(a,b)=(a+b)/2$ and $Q(a,b)=\sqrt{(a^{2}+b^{2})/2}$ are the Toader, arithmetic, and quadratic means of a and b, respectively.

Slavko Simic - One of the best experts on this subject based on the ideXlab platform.