Necessary convexity conditions for the Hahn-Banach theorem in metrizable spaces
نویسندگان
چکیده
منابع مشابه
Hahn-banach Theorem
We prove a version of Hahn-Banach Theorem. and 1] provide the notation and terminology for this paper. The following propositions are true: (1) For all sets x, y and for every function f such that h hx; yi i 2 f holds y 2 rng f: (2) For every set X and for all functions f, g such that X dom f and f g holds fX = gX: (3) For every non empty set A and for every set b such that A 6 = fbg there exis...
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(2)1 For every set X and for all functions f , g such that X ⊆ dom f and f ⊆ g holds f X = g X . (3) For every non empty set A and for every set b such that A 6= {b} there exists an element a of A such that a 6= b. (4) For all sets X , Y holds every non empty subset of X→̇Y is a non empty functional set. (5) Let B be a non empty functional set and f be a function. Suppose f = ⋃ B. Then dom f = ⋃...
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ژورنال
عنوان ژورنال: Pacific Journal of Mathematics
سال: 1973
ISSN: 0030-8730,0030-8730
DOI: 10.2140/pjm.1973.44.715