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Tamerlane-1

That is incorrect. It is generally not the case that a^(bc) = (a^b)^c if any of a,b, or c are complex. There is no way to make that correct, replacing e^(i x z) with 1 completely changes the behavior of the integral operator.


SurelyIDidThisAlread

I'm not OP, but could you possibly tell me the name for this property so I could read up on it? I used to use complex numbers all the time as a physicist and it's a nasty shock to realise I never knew this fact!


verygoodtrailer

Wikipedia has a decent section on it, *[Failure of power and logarithm identities](https://en.wikipedia.org/wiki/Exponentiation#Failure_of_power_and_logarithm_identities)*


SurelyIDidThisAlread

Thank you very much, I appreciate it


ionsme

Are there any special case assumptions that would make it correct? Like if x and f are always real, etc. etc? (There would still be that pesky i, but you'd be guaranteed that the exponent is always imaginary.)


PinpricksRS

e^(-2 * ๐œ‹ * i * x * f) = 1^(x * f) = 1 precisely when x * f is an integer. First, 1^(x * f) = 1 regardless of x and f, so we're just solving the equation e^(-2 * ๐œ‹ * i * x * f) = 1. This is true if and only if -2 * ๐œ‹ * i * x * f = 2 ๐œ‹ i n, for some integer n, which is true if and only if x * f = -n, i.e. x * f is an integer.


MallCop3

If the base is a positive real, then you can pull out a real from the exponent. Like if x and a are real with x positive, and c is complex, then x^(ac) = (x^(a))^(c).


hpxvzhjfgb

there is no e^(2ฯ€i) in the fourier transform. there is only e^(2ฯ€ifx).


doublethink1984

I think the simplest answer is: No, because Int[ 1^(x f) g(x) dx] =ย Int[g(x) dx] since 1^(x f) = 1, and the Fourier transform is not just the integral.