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Stone-Weierstrass theorem (Theorem)

Let $ X$ be a compact space and let $ C^0(X,\mathbb{R})$ be the algebra of continuous real functions defined over $ X$. Let $ \mathcal{A}$ be a subalgebra of $ C^0(X,\mathbb{R})$ for which the following conditions hold:

  1. $ \forall x, y \in X, x \ne y, \exists f \in \mathcal{A} : f(x) \neq f(y)$
  2. $ 1 \in \mathcal{A}$
Then $ \mathcal{A}$ is dense in $ C^0(X,\mathbb{R})$.

This theorem is a generalization of the classical Weierstrass approximation theorem to general spaces.



"Stone-Weierstrass theorem" is owned by rspuzio. [ full author list (2) | owner history (1) ]
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proof of Stone-Weierstrass theorem (Proof) by rspuzio
Stone-Weierstrass theorem (complex version) (Theorem) by asteroid
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Cross-references: Weierstrass approximation theorem, dense in, subalgebra, real functions, continuous, algebra, compact
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This is version 6 of Stone-Weierstrass theorem, born on 2002-06-01, modified 2008-05-04.
Object id is 2984, canonical name is StoneWeierstrassTheorem.
Accessed 5250 times total.

Classification:
AMS MSC46E15 (Functional analysis :: Linear function spaces and their duals :: Banach spaces of continuous, differentiable or analytic functions)

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