2022-04-17

58: Derivation at Point of \(C^k\) Functions

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A definition of derivation at point of \(C^k\) functions

Topics


About: \(C^\infty\) manifold with boundary

The table of contents of this article


Starting Context



Target Context


  • The reader will have a definition of derivation at point of \(C^k\) functions.

Orientation


There is a list of definitions discussed so far in this site.

There is a list of propositions discussed so far in this site.


Main Body


1: Definition


For any \(C^\infty\) manifold with (possibly empty) boundary, \(M\), and any point, \(p \in M\), any \(\mathbb{R}\)-linear map, \(D_v: C^k_p (M) \to \mathbb{R}\), that satisfies the Leibniz rule, \(D_v (f_1 f_2) = D_v (f_1) f_2 (p) + f_1 (p) D_v (f_2)\)


2: Note


Strictly speaking, \(C^\infty\) manifold with boundary is not required for \(k \neq \infty\), but just topological manifold with boundary does not suffice, because \(C^k\)-ness is not defined there.


References


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