Two sharp inequalities for power mean, geometric mean, and harmonic mean.
The author generalizes Stolarsky's Extended Mean Values to a four-parameter family of means F(r,s;a,b;x,y) = E(r,s;ax,by)/E(r,s;a,b) and investigates their monotonicity properties.
We present some properties of mixture and generalized mixture operators, with special stress on their monotonicity. We introduce new sufficient conditions for weighting functions to ensure the monotonicity of the corresponding operators. However, mixture operators, generalized mixture operators neither quasi-arithmetic means weighted by a weighting function need not be non- decreasing operators, in general.