Limit of a sequence: Difference between revisions

From Citizendium
Jump to navigation Jump to search
imported>Igor Grešovnik
m (Started the article)
 
imported>Igor Grešovnik
m (added definition)
Line 1: Line 1:
The [[Mathematics|mathematical]] concept of '''limit of a sequence''' provides a rigorous definition of the idea of a sequence converging towards a point called the limit.
The [[Mathematics|mathematical]] concept of '''limit of a sequence''' provides a rigorous definition of the idea of a sequence converging towards a point called the limit.
Suppose ''x''<sub>1</sub>, ''x''<sub>2</sub>, ... is a [[sequence]] of [[Real number|real numbers]].
We say that the real number ''L'' is the ''limit'' of this sequence and we write
:<math> \lim_{n \to \infty} x_n = L </math>
[[if and only if]] for every [[real number]] &epsilon; > 0 there exists a [[natural number]] ''n''<sub>0</sub> such that for all ''n'' > ''n''<sub>0</sub> we have  |''x''<sub>''n''</sub>&nbsp;&minus;&nbsp;''L''| < &epsilon;. The number ''n''<sub>0</sub> will in general depend on &epsilon;.

Revision as of 20:31, 23 November 2007

The mathematical concept of limit of a sequence provides a rigorous definition of the idea of a sequence converging towards a point called the limit.

Suppose x1, x2, ... is a sequence of real numbers. We say that the real number L is the limit of this sequence and we write

if and only if for every real number ε > 0 there exists a natural number n0 such that for all n > n0 we have |xn − L| < ε. The number n0 will in general depend on ε.