Difference between revisions of "Exponential"

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Let $a$ be constant. Exponential functions are of the form
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The exponential function $\exp \colon \mathbb{C} \rightarrow \mathbb{C}$ is defined by the formula
$$f(x)=a^x.$$
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$$\exp(z) = e^z = \sum_{k=0}^{\infty} \dfrac{x^k}{k!},$$
The most commonly used exponential function is $e^x$, where $e$ is the [[E | base of the natural logarithm]]. It can be characterized as the unique solution to the initial value problem
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where $e$ is the [[E | base of the natural logarithm]]. It can be characterized as the unique solution to the initial value problem
 
$$\left\{ \begin{array}{ll}
 
$$\left\{ \begin{array}{ll}
 
y'=y \\
 
y'=y \\
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\end{array} \right.$$
 
\end{array} \right.$$
  
[[File:Complex exp.jpg|500px]]
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<div align="center">
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<gallery>
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File:Exp.png|Graph of $\mathrm{arccos}$ on $\mathbb{R}$.
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File:Complex exp.jpg|[[Domain coloring]] of [[analytic continuation]] of $\exp$.
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</gallery>
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</div>
  
[[File:Complex Exp minus z squared.jpg|500px]]
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[[500px]]

Revision as of 14:04, 1 November 2014

The exponential function $\exp \colon \mathbb{C} \rightarrow \mathbb{C}$ is defined by the formula $$\exp(z) = e^z = \sum_{k=0}^{\infty} \dfrac{x^k}{k!},$$ where $e$ is the base of the natural logarithm. It can be characterized as the unique solution to the initial value problem $$\left\{ \begin{array}{ll} y'=y \\ y(0)=1. \end{array} \right.$$

500px