‎Some improvements of Young inequality and its reverse for positive‎ ‎numbers with Kantorovich constant $K(t‎, ‎2)=frac{(1+t)^2}{4t}$‎ ‎are given‎. ‎Using these inequalities some operator inequalities and‎ ‎Hilbert-Schmidt norm versions for matrices are proved‎. ‎In‎ ‎particular‎, ‎it is shown that if $a‎, ‎b$ are positive numbers and‎ ‎$0 leqslant nu leqslant 1,$ then for all integers $ kgeqsl...

In this paper, we present some operator and eigenvalue inequalities involving monotone, doubly concave convex functions. These provide variants of Acz\'{e}l inequality its reverse via generalized Kantorovich constant.

The convergence properties of Newton’s method for systems of equations with constant rank derivatives are studied under the hypothesis that the derivatives satisfy some weak Lipschitz conditions. The unified convergence results, which include Kantorovich type theorems and Smale’s point estimate theorems as special cases, are obtained. Mathematics subject classification: 49M15, 65F20, 65H10.