From Euler's identity: i^i=exp(-pi/2)= 0.2079 (rounded)

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In summary, the conversation discusses Euler's identity, which states that i^i has a value of exp(-pi/2) or approximately 0.2079. However, this value is not specific and can be expressed as e^{i^2(\frac{\pi}{2}+2\pi \cdot n) } for all integers n. There is also discussion about the use of ^ as raising to a power and the multi-valued mapping of the complex logarithm. The conversation concludes with a suggestion to use "tex" tags and latex syntax for equations in future posts.
  • #1
SW VandeCarr
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From Euler's identity: i^i=exp(-pi/2)= 0.2079 (rounded). I've always thought of this as an interesting result although I don't know of any particular significance or consequence of it. Is there any?
 
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  • #2


i^i does not have a specific value. [tex]i^i=e^{i^2(\frac{\pi}{2}+2\pi \cdot n) }=e^{-(\frac{\pi}{2}+2\pi \cdot n) }[/tex] for all integers n.
 
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  • #3


Jarle said:
i^i does not have a specific value. [tex]i^2=e^{i^2(\frac{\pi}{2}+2\pi \cdot n) }=e^{-(\frac{\pi}{2}+2\pi \cdot n) }[/tex] for all integers n.

I'm using ^ as raising to a power except for 'exp' where exp(x) means e^x

exp(i pi)= -1

SQRT [exp(i pi) = SQRT (-1)

exp(i pi/2) = i

exp ((i^2) pi/2)) = i^i = exp (-pi/2) = 0.2079 (rounded)
 
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  • #4


SW VandeCarr:

Jarle is also using it in that sense.

However, as he pointed out, the complex logarithm is a multi-valued mapping, in contrast to the real logarithm.
 
  • #5


arildno said:
SW VandeCarr:

Jarle is also using it in that sense.

However, as he pointed out, the complex logarithm is a multi-valued mapping, in contrast to the real logarithm.

Thanks, but the algebra is correct, is it not? Normally I don't see the +2pi.n term in texts.
 
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  • #6


Strange, I do!
 
  • #7


SW VandeCarr - you can put "tex" tags around your equations and use latex syntax instead of defining all of your notation. It makes yours and everyone else's life easier :)
 
  • #8


daviddoria said:
SW VandeCarr - you can put "tex" tags around your equations and use latex syntax instead of defining all of your notation. It makes yours and everyone else's life easier :)

Thanks daviddoria. I guess it's about time I started using latex if I'm going to be posting questions here.
 

Related to From Euler's identity: i^i=exp(-pi/2)= 0.2079 (rounded)

1. What is Euler's identity?

Euler's identity is a mathematical equation that relates five important mathematical constants: e (the base of the natural logarithm), π (pi), i (the imaginary unit), 1 (the multiplicative identity), and 0 (the additive identity). The equation is written as e^(iπ) + 1 = 0 and is considered one of the most beautiful and profound mathematical equations.

2. What is the value of i^i?

The value of i^i is approximately 0.2079 (rounded). This can also be written as e^(-π/2) or cos(π/2) ≈ 0.2079, where e is the base of the natural logarithm and π is pi.

3. How is i^i calculated?

To calculate i^i, you can use the formula e^(i*ln(i)), where e is the base of the natural logarithm and ln is the natural logarithm function. In this case, ln(i) = π/2i. Substituting this into the formula gives us e^(i*π/2i). Using Euler's formula, we can rewrite this as cos(π/2) + i*sin(π/2) = 0 + i = i. Therefore, i^i = e^(i*π/2i) = e^(i) = cos(π/2) + i*sin(π/2) = 0 + i = i.

4. Why is i^i a real number?

Even though i^i is raised to a complex power, it still results in a real number. This is because of the relationship between complex numbers and exponential functions. When a complex number is raised to a complex power, the result is a real number. In the case of i^i, the imaginary part of the result is 0, making it a real number.

5. What is the significance of i^i in mathematics?

i^i is significant in mathematics because it is an example of how seemingly unrelated mathematical concepts can be connected through a single equation. It also highlights the deep connections between trigonometry, complex numbers, and exponential functions. Furthermore, it has practical applications in fields such as physics and engineering.

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