Bulletin of the Korean Mathematical Society (대한수학회보)

Korean Mathematical Society (대한수학회)
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TWO NEW PROOFS OF THE COMPLETE MONOTONICITY OF A FUNCTION INVOLVING THE PSI FUNCTION

  • Guo, Bai-Ni (School of Mathematics and Informatics, Henan Polytechnic University) ;
  • Qi, Feng (Department of Mathematics, College of Science, Tianjin Polytechnic University)
  • Published : 2010.01.31
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Abstract

In the present paper, we give two new proofs for the necessary and sufficient condition $\alpha\leq1$ such that the function $x^{\alpha}[lnx-\psi(x)]$ is completely monotonic on (0,$\infty$).

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References

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