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extreme point (Definition)
Definition 1   Let $ C$ be a convex subset of a vector space $ X$. A point $ x \in C$ is called an extreme point if it is not an interior point of any line segment in $ C$. That is $ x$ is extreme if and only if whenever $ x = ty +(1-t)z$, $ t \in (0,1)$, $ z \not= y$, implies either $ y \notin C$ or $ z \notin C$.

For example the set $ [0,1] \in {\mathbb{R}}$ is a convex set and 0 and $ 1$ are the extreme points.

Bibliography

1
H. L. Royden. Real Analysis. Prentice-Hall, Englewood Cliffs, New Jersey, 1988



"extreme point" is owned by jirka.
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See Also: face of a convex set, exposed points are dense in the extreme points

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Cross-references: convex set, implies, line segment, interior point, point, vector space, convex subset
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This is version 4 of extreme point, born on 2004-06-15, modified 2006-10-06.
Object id is 5920, canonical name is ExtremePoint.
Accessed 5069 times total.

Classification:
AMS MSC52A99 (Convex and discrete geometry :: General convexity :: Miscellaneous)

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