Steiner's problem

Steiner's problem

Steiner's problem is the problem of finding the maximum of the function

: f(x)=x^{1/x}.,

It is named after Jakob Steiner.

The maximum is at x=e, where "e" denotes the base of natural logarithms. One can determine that by solving the equivalent problem of maximizing

: g(x)=ln f(x) = frac{ln x}{x}.

The derivative of g can be calculated to be

: g'(x)= frac{1-ln x}{x^2}.

It follows that g'(x) is positive for 0 and negative for x>e, which implies that g(x) (and therefore f(x)) increases for 0 and decreases for x>e. In conclusion, x=e is the unique global maximum of f(x).


Wikimedia Foundation. 2010.

Игры ⚽ Нужна курсовая?

Look at other dictionaries:

  • Steiner tree problem — Steiner tree for three points A, B, and C (note there are no direct connections between A, B, C). The Steiner point S is located at the Fermat point of the triangle ABC …   Wikipedia

  • Steiner tree — The Steiner tree problem, named after Jakob Steiner, is a problem in combinatorial optimization.The Steiner tree problem is superficially similar to the minimum spanning tree problem: given a set V of points (vertices), interconnect them by a… …   Wikipedia

  • Steiner Tree — Das Steinerbaumproblem (oft mit STEINER TREE notiert), ein nach dem Schweizer Mathematiker Jakob Steiner benanntes Problem der Graphentheorie, ist eine Verallgemeinerung des Problems des minimalen Spannbaums. Beim Steinerbaumproblem sucht man in… …   Deutsch Wikipedia

  • Steiner points — There are two uses of the term Steiner point.In graph theory and computational geometry, a Steiner point is an extra vertex that is not a member of the input. For example, see their use in the Steiner tree problem.In geometry, a Steiner point is… …   Wikipedia

  • Problem of Apollonius — In Euclidean plane geometry, Apollonius problem is to construct circles that are tangent to three given circles in a plane (Figure 1); two circles are tangent if they touch at a single point. Apollonius of Perga (ca. 262 BC ndash; ca. 190 BC)… …   Wikipedia

  • Steiner chain — In geometry, a Steiner chain is a set of n circles, all of which are tangent to two given non intersecting circles (blue and red in Figure 1), where n is finite and each circle in the chain is tangent to the previous and next circles in the chain …   Wikipedia

  • Steiner system — In combinatorial mathematics, a Steiner system (named after Jakob Steiner) is a type of block design.A Steiner system with parameters l , m , n , written S( l , m , n ), is an n element set S together with a set of m element subsets of S (called… …   Wikipedia

  • Problem des Übels — Theodizee [ˌteodiˈt͜seː] (frz. théodicée, v. altgriech. θεός theós „Gott“ und δίκη díke „Gerechtigkeit“) heißt „Rechtfertigung Gottes“. Das Theodizeeproblem ist ein klassisches philosophisches und theologisches Problem für diejenigen religiösen… …   Deutsch Wikipedia

  • Steiner-Tripel-System — Ein Blockplan ist eine Inzidenzstruktur, die insbesondere in der endlichen Geometrie, der Kombinatorik, sowie der statistischen Versuchsplanung von Bedeutung ist. Inhaltsverzeichnis 1 Definition 2 Beispiele und Eigenschaften 2.1 Parallelismen und …   Deutsch Wikipedia

  • Steinerbaum-Problem — Das Steinerbaumproblem (oft mit STEINER TREE notiert), ein nach dem Schweizer Mathematiker Jakob Steiner benanntes Problem der Graphentheorie, ist eine Verallgemeinerung des Problems des minimalen Spannbaums. Beim Steinerbaumproblem sucht man in… …   Deutsch Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”