Tangencies for Power Functions with Integer Exponent

Authors

  • Cairo Henrique Vaz Cotrim Universidade de Sao Paulo, Campus Sao Carlos, Brasil.
  • Laredo Rennan Pereira Santos Instituto Federal de Educacao, Ciencia e Tecnologia de Goías, Campus Formosa, Brasil.

DOI:

https://doi.org/10.17268/sel.mat.2025.01.13

Keywords:

Power Function, Tangency, Binomial Theorem

Abstract

Considering a power function f(x) = x^n with exponent n as a positive integer, we show that, at each of its points, there exists a unique polynomial function of degree n − 1 that is tangent to it at that point. Similarly, we verify that every power function h(x) = x^k with exponent k as a negative integer is tangent, at each of its points, to a function of the form l(x) =Sa^t.x^t, where the exponents t are integers between k + 1 and −1.

References

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Published

2025-07-26

How to Cite

Vaz Cotrim, C. H., & Pereira Santos, L. R. (2025). Tangencies for Power Functions with Integer Exponent. Selecciones Matemáticas, 12(01), 155 - 161. https://doi.org/10.17268/sel.mat.2025.01.13

Issue

Section

Communications