Let be a non-negative increasing differentiable function and a non-negative function such that the quotient is non-decreasing. Then the function
is log-concave. If and the quotient is non-increasing, then the function is log-convex.
Cite this article
S. Varošanec, J. Pečarić, Gauss’ and Related Inequalities. Z. Anal. Anwend. 14 (1995), no. 1, pp. 175–183