the main goal of this paper is the study of the generalized hyers-ulam stability of the following functionalequation f (2x  y)  f (2x  y)  (n 1)(n  2)(n  3) f ( y)  2n2 f (x  y)  f (x  y)  6 f (x) where n  1,2,3,4 , in non–archimedean spaces, by using direct and fixed point methods.

In this paper, a concept of generalized weakly contraction mappings in partially ordered fuzzy metric spaces is introduced and  coincidence point  theorems on partially ordered fuzzy metric spaces are proved. Also, as the corollary of these theorems, some common fixed point theorems on partially ordered fuzzy metric spaces are presented.

Darbo fixed point theorem is a powerful tool which used in many fields mathematics. Because of this feature, generalizations and its relations with other subjects have been investigated. Here we introduce generalization an F - contraction type mapping define new by using both function lasses uniformly convergent sequences functions examine some properties. Afterward, show that the contraction, ...

begin{abstract} If $F,D:Rto R$ are additive mappings which satisfy $F(x^{n}y^{n})=x^nF(y^{n})+y^nD(x^{n})$ for all $x,yin R$. Then, $F$ is a generalized left derivation with associated Jordan left derivation $D$ on $R$. Similar type of result has been done for the other identity forcing to generalized derivation and at last an example has given in support of the theorems. end{abstract}

We consider the generalized Tolman solution of general relativity, describing evolution a spherical dust cloud in presence an external electric or magnetic field. The contains three arbitrary functions f(R), F(R) and τ0(R), where R is radial coordinate comoving reference frame. splits into branches corresponding to hyperbolic (f>0), parabolic (f=0) elliptic (f<0) types motion. In such mod...

where Y0 is a (N 1) vector of observations, X0 is a (N k) full rank matrix of known constants, is a (k 1) vector of unknown parameters, and "0 is a (N 1) vector of randomly distributed Gaussian errors with E("0) = 0 and V ar("0) = IN : The least squares estimate of is ̂ = (X 0 0X0) X 0 0Y0: The basic idea in in uence analysis as introduced by Cook (1977) concerns the stability of a linear regre...