How does the function f(x)=0^{-x} behave for positive and complex numbers?

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zetafunction
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how this function [tex]f(x)= 0^{-x}[/tex]

should be understood? , if x is NEGATIVE, we find no problems, since 0 raised to any power is 0

but how about x being a positive real number ? , or x being a PURE COMPLEX or complex number ?

could we consider a 'regularization' to this f(x) so [tex]f(x)_{reg}=0[/tex] is always 0
 
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I would imagine the same way you would understand [tex]\sqrt{x}[/tex]. It's assumed that the domain is restricted only to numbers that make sense.

If you have some context where you think you really need to plug 1 into the function, you should post the full setup here
 
In the real case, the function

[tex]f(x,y)=y^x=e^{x\log y}[/tex]

is defined only for [tex]y>0[/tex]

In the complex case, put

[tex]y=\rho e^{i\alpha}\qquad\textrm{and}\qquad x=a+ib[/tex]

then

[tex]y^x=(\rho e^{i\alpha})^{(a+ib)}[/tex]

and, after some calculations, you find

[tex]y^x=Re^{i\beta}[/tex]

with

[tex]R=\rho^ae^{-\alpha b}\qquad\textrm{and}\qquad\beta=b\log\rho+\alpha a[/tex]

So in the complex case you must have [tex]\rho\neq 0[/tex], which means [tex]y\neq 0[/tex].

I hope I didn't meke calculation errors...try it yourself! :redface:
 
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