Is x^pi Real for Negative Values of x?

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The discussion addresses whether x^π is real for negative values of x, concluding that it is not. Both x^π and x^e are real only for x ≥ 0, and their plots appear similar, but this does not imply that π is an odd number. The expression (-x)^π results in a complex number due to the factor (-1)^π, which is not real. The discussion emphasizes that for any power x^α, the conditions for it being real or complex for negative x can be analyzed similarly, although rational exponents introduce additional complexity. Thus, x^π is not defined as a real number for negative x.
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The plot of x^(pi) looks like an odd function, does that make pi an odd number?

http://www.wolframalpha.com/input/?i=x^pi

same goes for x^e

http://www.wolframalpha.com/input/?i=x^e
 
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Those functions are real for x\geq 0 only. If you take a look at that interval for both odd and even functions, you'll realize that you can't really tell a difference between their shape.
And no it doesn't make pi an odd number.
 
the definition of an odd number n is a number that's able to be expressed as n=2k+1 for some integer k. use that definition to see if pi is an odd number.
 
Mentallic said:
Those functions are real for x\geq 0 only. If you take a look at that interval for both odd and even functions, you'll realize that you can't really tell a difference between their shape.
And no it doesn't make pi an odd number.
why is that true?
 
mxbob468 said:
why is that true?

Because if we take some positive number x, then (-x)^{\pi}=(-1)^{\pi}\cdot x^{\pi}
Since x is positive, x^{\pi}>0 so we just have to deal with the (-1)^{\pi} factor. It is complex, but if you want a proof of this, simply convert it into its complex form:

e^{i\pi}=-1 therefore (-1)^{\pi}=e^{i\pi ^2}=cos(\pi ^2)+isin(\pi ^2) so if it is to be a real number, then the sin of \pi ^2 needs to be equal to 0, but this isn't the case.

In fact we can take any power x^{\alpha}, and deduce the circumstances whether it will be real or complex for negative values of x by following a similar process. But be wary, it is a little more complicated dealing with all rational values.
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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