TWO NEW PROOFS OF THE COMPLETE MONOTONICITY OF A FUNCTION INVOLVING THE PSI FUNCTION

Title & Authors
TWO NEW PROOFS OF THE COMPLETE MONOTONICITY OF A FUNCTION INVOLVING THE PSI FUNCTION
Guo, Bai-Ni; Qi, Feng;

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