設X和Y為兩個不同的 L-凸空間。本論文探討兩個分別由X映到Y和由Y映到X之多值函數的一些同值點定理。我們並利用上述的結果證明大中取小不等式及大中取小等式的存在性定理。本文的結果推廣了許多學者的一些研究結果。

In this paper, we establish some coincidence theorems of two set-valued functions defined on two L-convex spaces. As applications, we use the above theorems to get the existence theorems concerning minimax inequalities and minimax equalities. Our results generalize many other authors’ results (see, for example, [1],[5] ).

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