Difference between revisions of "Taylor Series"

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(New Concept: Taylor Series)
(New Concept: Taylor Series)
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== New Concept: Taylor Series ==
 
== New Concept: Taylor Series ==
  
Think of Taylor series as a special kind of power series, where the sequence of partial sums are meant as better and better approximations of some other function.
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* Think of Taylor series as a special kind of power series, where the sequence of partial sums are meant as better and better approximations of some other function.
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* The Taylor Series is derived from the function.
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Definition from
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The Taylor series of a [[real number|real]] or [[complex number|complex]] function ''ƒ''(''x'') that is [[Infinitely differentiable function|infinitely differentiable]] in a [[Neighborhood (mathematics)|neighborhood]] of a [[real number|real]] or [[complex number]] ''a'' is the [[power series]]
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<!--
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As stated below, the Taylor series need not equal the function. So please don't write f(x)=... here. In other words,
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DO NOT CHANGE ANYTHING ABOUT THIS FORMULA-->:<math>f(a)+\frac {f'(a)}{1!} (x-a)+ \frac{f''(a)}{2!} (x-a)^2+\frac{f^{(3)}(a)}{3!}(x-a)^3+ \cdots. </math><!--
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-->
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which can be written in the more compact [[sigma notation]] as
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:<math> \sum_{n=0} ^ {\infin } \frac {f^{(n)}(a)}{n!} \, (x-a)^{n}</math>
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where ''n''! denotes the [[factorial]] of ''n'' and ''ƒ''<sup>&nbsp;(''n'')</sup>(''a'') denotes the ''n''th [[derivative]] of ''ƒ'' evaluated at the point ''a''. The zeroth derivative of ''ƒ'' is defined to be ''ƒ'' itself and {{nowrap|(''x'' &minus; ''a'')<sup>0</sup>}} and 0! are both defined to be&nbsp;1. In the case that {{nowrap|''a'' {{=}} 0}}, the series is also called a '''Maclaurin series'''.

Revision as of 20:43, 14 March 2011

Review Concepts

  • Sequences
  • Convergence
  • Infinite series
  • The sequence of partial sums of an infinite series
  • Power series

New Concept: Taylor Series

  • Think of Taylor series as a special kind of power series, where the sequence of partial sums are meant as better and better approximations of some other function.
  • The Taylor Series is derived from the function.

Definition from

The Taylor series of a real or complex function ƒ(x) that is infinitely differentiable in a neighborhood of a real or complex number a is the power series

f(a)+\frac {f'(a)}{1!} (x-a)+ \frac{f''(a)}{2!} (x-a)^2+\frac{f^{(3)}(a)}{3!}(x-a)^3+ \cdots.

which can be written in the more compact sigma notation as

 \sum_{n=0} ^ {\infin } \frac {f^{(n)}(a)}{n!} \, (x-a)^{n}

where n! denotes the factorial of n and ƒ (n)(a) denotes the nth derivative of ƒ evaluated at the point a. The zeroth derivative of ƒ is defined to be ƒ itself and Template:Nowrap and 0! are both defined to be 1. In the case that Template:Nowrap, the series is also called a Maclaurin series.