Generalized projections, decompositions, and the Pythagorean-type theorem in Banach spaces
نویسندگان
چکیده
منابع مشابه
A Pythagorean Approach in Banach Spaces
Let X be a Banach space and let S(X)= {x ∈ X , ‖x‖ = 1} be the unit sphere of X . Parameters E(X) = sup{α(x), x ∈ S(X)}, e(X) = inf{α(x), x ∈ S(X)}, F(X) = sup{β(x), x ∈ S(X)}, and f (X) = inf{β(x), x ∈ S(X)}, where α(x) = sup{‖x + y‖2 + ‖x − y‖2, y ∈ S(X)}, and β(x) = inf{‖x + y‖2 + ‖x− y‖2, y ∈ S(X)} are introduced and studied. The values of these parameters in the lp spaces and function spac...
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ژورنال
عنوان ژورنال: Applied Mathematics Letters
سال: 1998
ISSN: 0893-9659
DOI: 10.1016/s0893-9659(98)00112-8