Limit of a function: Difference between revisions

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In [[mathematics]], the concept of a '''limit''' is used to describe the behavior of a [[function (mathematics)|function]] as its [[argument]] either "gets close" to some point, or as it becomes arbitrarily large.
In [[mathematics]], the concept of a '''limit''' is used to describe the behavior of a [[function (mathematics)|function]] as its [[argument]] either "gets close" to some point, or as it becomes arbitrarily large.
Suppose ''f''(''x'') is a [[real-valued function]] and ''a'' is a [[real number]]. The expression
:<math> \lim_{x \to a}f(x) = L </math>
means that ''f''(''x'') can be made arbitrarily close to ''L'' by making ''x'' sufficiently close to ''a''.  We say that "the limit of the function ''f'' of ''x'', as ''x'' approaches ''a'', is ''L''". 
Limit of a function can in some cases be defined even at values of the argument at which the function itself is not defined. For example,
:<math> \lim_{x \to 0}\frac{sin(x)}{x} = 1 , </math>
although the function
:<math> f(x)=\frac{sin(x)}{x} </math>
is not defined at ''x''=0.





Revision as of 20:15, 23 November 2007

In mathematics, the concept of a limit is used to describe the behavior of a function as its argument either "gets close" to some point, or as it becomes arbitrarily large.

Suppose f(x) is a real-valued function and a is a real number. The expression

means that f(x) can be made arbitrarily close to L by making x sufficiently close to a. We say that "the limit of the function f of x, as x approaches a, is L".

Limit of a function can in some cases be defined even at values of the argument at which the function itself is not defined. For example,


although the function

is not defined at x=0.


See also