Solving inequalities using radical and adjacent functions
https://doi.org/10.22405/2226-8383-2024-25-3-70-85
Abstract
Within the framework of the nonlinear method of angular boundary functions, the existence of solutions to nonlinear boundary value problems is proven through the construction of barrier functions. Barrier functions are constructed through specially designated support barriers. The support barriers themselves can also act as barrier functions. In this case, it is necessary to prove the fulfillment of certain inequalities that are of independent functional interest. The study of these inequalities leads to cumbersome calculations. This paper proposes a method that significantly simplifies obtaining results. Possible solutions to inequalities are constructed
in the form of polynomials. The initial stage involves identifying the polynomial of the highest degree of interest. Such a polynomial is called radical. Next, polynomials of lower degrees, called adjacent polynomials, are successively added to the radical polynomial.
About the Authors
Alexey Igorevich DenisovRussian Federation
postgraduate student
Igor Vasil’evich Denisov
Russian Federation
doctor of physical and mathematical sciences, professor
References
1. Denisov, I. V., 2017, “Angular Boundary Layer in Boundary Value Problems for Singularly
2. Perturbed Parabolic Equations with Quadratic Nonlinearity”, Computational Mathematics and
3. Mathematical Physics, Vol. 57. No. 2. pp. 253–271.
4. Denisov, I. V., 2021 “Corner Boundary Layer in Boundary Value Problems for Singularly
5. Perturbed Parabolic Equations with Cubic Nonlinearities”, Computational Mathematics and
6. Mathematical Physics, Vol. 61. No. 2. pp. 242-–253.
7. Denisov, A. I., Denisov, I. V., 2024, “Nonlinear method of angular boundary functions for
8. singularly perturbed parabolic problems with cubic nonlinearities”, Chebyshevskii Sbornik, vol. 25, no. 1, pp. 25–40.
9. Denisov, I. V., 2021, “Corner Boundary Layer in Boundary Value Problems with Nonlinearities Having Stationary Points”, Computational Mathematics and Mathematical Physics, Vol. 61. No. 11. pp. 1855–1863.
10. Denisov, A. I., Denisov, I. V., 2023, “Nonlinear method of angular boundary functions in
11. problems with cubic nonlinearities”, Chebyshevskii Sbornik, vol. 24, no. 1, pp. 27–39.
12. Denisov, I. V., 2000, “On classes of functions defined by functional inequalities”, Izvestiya of Tula State University. Series “Mathematics. Mechanics. Computer Science”, vol. 6. no. 1, pp. 79–84.
13. Denisov, I. V., 2009, “About some classes of functions”, Chebyshevskii Sbornik, vol. 10, no. 2, pp. 79–108.
14. Denisov, A. I., Denisov, I. V., 2024, “The support barrier functions for nonlinear parabolic
15. problems”, Chebyshevskii Sbornik, vol. 25, no. 1, pp. 235–242.
Review
For citations:
Denisov A.I., Denisov I.V. Solving inequalities using radical and adjacent functions. Chebyshevskii Sbornik. 2024;25(3):70-85. (In Russ.) https://doi.org/10.22405/2226-8383-2024-25-3-70-85