How to draw the graphs of the Exponential, Logistic, and Gaussian functions with pencil and ruler in an accurate way

Authors

DOI:

https://doi.org/10.22199/issn.0717-6279-5936

Keywords:

piecewise constant argument, numerical integration, approximation of solutions, exponential function

Abstract

In this work, we will give a novel method to construct a continuous approximation of the Exponential, Logistic, and Gaussian functions that allow us to do a handmade drawing of their graphs for which there is no accuracy of drawing at elementary levels (even at advanced ones!). This method arises from solving the elementary ordinary differential equation x0 (t) = ax(t) combined with a suitable piecewise constant argument. The proposed approximation will allow us to generate several numerical schemes in an elementary way, generalizing the classical ones as, Euler’s schemes. No sophisticated mathematical tools are needed.

Author Biographies

Ricardo Torres Naranjo, Universidad Austral de Chile.

Instituto de Ciencias Físicas y Matemáticas, Facultad de Ciencias.

Samuel Castillo, Universidad del Bío-Bío.

Grupo de Investigación en Sistemas Dinámicos y Aplicaciones (GISDA), Departmento de Matemáticas, Facultad de Ciencias.

Manuel Pinto, Universidad de Chile.

Departamento de Matemáticas, Facultad de Ciencias.

References

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R. Torres, M. Pinto, S. Castillo and M. Kostic, “An uniform approximation of an impulsive cnn-hopfield type system by an impulsive differential equation with piecewise constant argument of generalized type on [γ,∞)”, Acta Appl. Math., vol. 8, no. 171, pp. 1-15, 2021.

Published

2023-11-27

How to Cite

[1]
R. F. Torres Naranjo, S. Castillo, and M. Pinto, “How to draw the graphs of the Exponential, Logistic, and Gaussian functions with pencil and ruler in an accurate way”, Proyecciones (Antofagasta, On line), vol. 42, no. 6, pp. 1653-1682, Nov. 2023.

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Section

Artículos