Smooth extensions of functions on separable Banach spaces
نویسندگان
چکیده
منابع مشابه
On the range of the derivative of Gâteaux-smooth functions on separable Banach spaces
We prove that there exists a Lipschitz function from l into IR which is Gâteaux-differentiable at every point and such that for every x, y ∈ l, the norm of f (x) − f (y) is bigger than 1. On the other hand, for every Lipschitz and Gâteaux-differentiable function from an arbitrary Banach space X into IR and for every ε > 0, there always exists two points x, y ∈ X such that ‖f (x)−f (y)‖ is less ...
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ژورنال
عنوان ژورنال: Mathematische Annalen
سال: 2009
ISSN: 0025-5831,1432-1807
DOI: 10.1007/s00208-009-0441-6