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| align="right" style="padding-right: 1em;" | || <math>\frac{x^m}{1-x} = \sum^{\infin}_{n=m} x^n\quad\mbox{ for }|x| < 1 \text{ and } m\in\mathbb{N}_0\!</math>
 
| align="right" style="padding-right: 1em;" | || <math>\frac{x^m}{1-x} = \sum^{\infin}_{n=m} x^n\quad\mbox{ for }|x| < 1 \text{ and } m\in\mathbb{N}_0\!</math>
 
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| align="right" style="padding-right: 1em;" | <SPAN STYLE="font-size: 8px;"> [[Formula_contributed_by_Anshita|credit]]</span> ||  
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[[Formula_contributed_by_Anshita|<math>\frac{x}{(1-x)^2} = \sum^{\infin}_{n=1}n x^n\quad\text{ for }|x| < 1\!</math> ]] <SPAN STYLE="font-size: 8px;"> [[Formula_contributed_by_Anshita|credit]]</span>
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[[Formula_contributed_by_Anshita|<math>\frac{x}{(1-x)^2} = \sum^{\infin}_{n=1}n x^n\quad\text{ for }|x| < 1\!</math> ]]
 
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! colspan="2" style="background: #eee;" | Other Series
 
! colspan="2" style="background: #eee;" | Other Series

Revision as of 15:12, 4 November 2009

Power Series Formulas
Series in symbolic forms
Taylor Series in one variable $ \sum_{n=0} ^ {\infin } \frac {f^{(n)}(a)}{n!} \, (x-a)^{n} $
Taylor Series in d variables

$ =\sum_{n_1=0}^{\infin} \cdots \sum_{n_d=0}^{\infin} \frac{(x_1-a_1)^{n_1}\cdots (x_d-a_d)^{n_d}}{n_1!\cdots n_d!}\,\left(\frac{\partial^{n_1 + \cdots + n_d}f}{\partial x_1^{n_1}\cdots \partial x_d^{n_d}}\right)(a_1,\dots,a_d).\! $

Taylor Series of certain functions
exponential $ e^x = \sum_{n=0}^\infty \frac{x^n}{n!}, $ $ \text{ for all } x\in {\mathbb C}\ $
logarithm

$ \ln(1+x) = \sum^{\infin}_{n=1} (-1)^{n+1}\frac{x^n}n,\text{ when }-1<x\le1 $

Geometric Series and related series
(info) Finite Geometric Series Formula $ \sum_{k=0}^n x^k = \left\{ \begin{array}{ll} \frac{1-x^{n+1}}{1-x}&, \text{ if } x\neq 1\\ n+1 &, \text{ else}\end{array}\right. $
(info) Infinite Geometric Series Formula $ \sum_{k=0}^n x^k = \left\{ \begin{array}{ll} \frac{1}{1-x}&, \text{ if } |x|\leq 1\\ \text{diverges} &, \text{ else }\end{array}\right. $
$ \frac{x^m}{1-x} = \sum^{\infin}_{n=m} x^n\quad\mbox{ for }|x| < 1 \text{ and } m\in\mathbb{N}_0\! $

$ \frac{x}{(1-x)^2} = \sum^{\infin}_{n=1}n x^n\quad\text{ for }|x| < 1\! $

Other Series
notes/name equation

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Alumni Liaison

Correspondence Chess Grandmaster and Purdue Alumni

Prof. Dan Fleetwood