In this paper, we give a negative

Abstract. In this paper, common fixed point theorems for Ciric type quasi-contractive mappings in b-metric spaces with Qt-functions are established. An example is also provided to support the common fixed point theorems. The main results presented in this paper improve and extend the corresponding results announced recently.

In this paper, we show that the sum of a compact convex subset and a simultaneously τ -strongly proximinal convex subset (resp. simultaneously approximatively τ -compact convex subset) of a Banach space X is simultaneously τ -strongly proximinal (resp. simultaneously approximatively τ -compact ), and the sum of a weakly compact convex subset and a simultaneously approximatively weakly compact convex subset of X is still simultaneously approximatively weakly compact, where τ is the norm or the weak topology. Moreover, some related results on the sum of simultaneously proximinal subspaces are presented.

No abstract

In this paper, we show that the sum of a compact convex subset and a simultaneously τstrongly proximinal convex subset (resp. simultaneously approximatively τ-compact convex subset) of a Banach space X is simultaneously τ-strongly proximinal (resp. simultaneously approximatively τcompact ), and the sum of weakly compact convex subset and a simultaneously approximatively weakly compact convex subset of X is still simultaneously approximatively weakly compact, where τ is the norm or the weak topology. Moreover, some related results on the sum of simultaneously proximinal subspaces are presented.

No abstract