“…This classical result has been extended in several directions: ultraspherical, Laguerre and Hermite polynomials [16], Jacobi polynomials [10,11], general class of polynomials [9], Bessel functions of the first kind [15], modified Bessel functions of the first kind [6,13,18], and so forth. This inequality still attracts the attention of mathematicians, and it is worth mentioning here that recently the inequality (1.1) was improved by Alzer et al [2].…”