Difference between revisions of "E"

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The number $e$ can be defined in the following way: let $f$ be the unique solution of the initial value problem
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The number $e$ is the number such that
$$y'=y;y(0)=1,$$
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$$\displaystyle\int_1^e \dfrac{1}{t} \mathrm{d}t=1.$$
then $e=f(1)$.
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This means, by definition, that $\log(e)=1$, where $\log$ denotes the [[logarithm]].
 
 
 
=Properties=
 
=Properties=
 
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Revision as of 06:48, 4 June 2016

The number $e$ is the number such that $$\displaystyle\int_1^e \dfrac{1}{t} \mathrm{d}t=1.$$ This means, by definition, that $\log(e)=1$, where $\log$ denotes the logarithm.

Properties

Theorem: The folllowing formula holds: $$e=\displaystyle\lim_{k \rightarrow \infty} \left( 1 + \dfrac{1}{k} \right)^k,$$ where $e$ denotes Euler's constant.

Proof:

Theorem: The real number $e$ is irrational.

Proof: proof goes here █

References

Who proved $e$ is irrational?