Difference between revisions of "179: e to the pi times i"

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{{comic
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| number    = 179
 
| date      = November 3, 2006
 
| title    = e to the pi times i
 
| image    = e_to_the_pi_times_i.png
 
| titletext = I have never been totally satisfied by the explanations for why e to the ix gives a sinusoidal wave.
 
}}
 
 
 
==Explanation==
 
The comic largely references {{w|Euler's identity}}. This identity states that e<sup>iπ</sup> + 1 = 0. Therefore, e<sup>iπ</sup> = &minus;1.
 
 
 
The humor from this comic is because of the seemingly arbitrary relationship between e, π, and the identity of i (the square root of &minus;1). e is the mathematical identity of which the derivative of e<sup>x</sup> with respect to x is still e<sup>x</sup>, while π is the relationship between the circumference of a circle divided by its diameter. Taking these two values and applying them to the value of i in such a manner makes it seem counter-intuitive  that it would yield &minus;1 from basic analysis. The above linked Wikipedia page goes into good detail of how to derive this identity, as does [https://www.youtube.com/watch?v=-dhHrg-KbJ0 this YouTube video].
 
 
 
The title text refers to how Euler's identity is called upon in complex form (separating real and imaginary numbers): e<sup>ix</sup> = cos(x) + i sin(x).
 
 
 
==Transcript==
 
:[Two Cueballs are standing at a board with writing on. One Cueball is pointing at the board.]
 
:Cueball: Numbers of the form n√-1 are "imaginary," but can still be used in equations.
 
:Friend: Okay.
 
:Cueball: And e^(π√-1)=-1.
 
:Friend: Now you're just fucking with me.
 
 
 
{{comic discussion}}
 
[[Category:Comics featuring Cueball]]
 
[[Category:Math]]
 

Revision as of 01:27, 5 May 2022

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