ISSN : 1226-0657
In the paper, by directly verifying an inequality which gives a lower bound for the first order modified Bessel function of the first kind, the authors supply a new proof for the complete monotonicity of a difference between the exponential function <TEX>$e^{1/t}$</TEX> and the trigamma function <TEX>${\psi}^{\prime}(t)$</TEX> on (0, <TEX>${\infty}$</TEX>).
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