Alternative proofs of Shafer's inequality for inverse hyperbolic tangent
arXiv:2103.14037 · doi:10.7153/jmi-2022-16-61
Abstract
We point out that a concise proof of Theorem 2 in the article, 'On a quadratic estimate of Shafer' by L. Zhu contains a small mistake. Correcting this mistake and giving alternative proofs of Theorem 2 is the main aim of this note.