Some classes of completely monotonic functions related to q gamma and q digamma functions
In the paper, some classes of completely monotonic functions involving the q gamma and q digamma functions are derived. The monotonicity properties of these functions are exploited to establish a double inequality for the ratio of the q gamma function and a double inequality for the q digamma function. Moreover, a class of inequalities for the q polygamma functions is presented. Mathematics subject classification (2010) 33D05, 26D15, 26A48.