How Do You Evaluate (1+i)^(1-i) and Describe the Set {1^x} for Real x?

cummings12332
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Homework Statement


Evaluate {(1+i)^(1-i)} and describe the set{1^x} when x is a real number, distinguish between the cases when x is rational and when x is rational. for now considering the complex number.

2. The attempt at a solution
i don't know how to start with,for firest part i just write it into e^((1-i)log(1+i)) then get the number with e to the power which inculding i , and the secound part , for 1=e^(i2npi) then 1^x is e^(2inxpi) then how to consider the case for rational and irrational here?????
 
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start by breaking the factor into two factors (1+i)^1 * (1+i)^(-i)
 
jedishrfu said:
start by breaking the factor into two factors (1+i)^1 * (1+i)^(-i)

i can do the first part now, many thanks ,but i don't understand the secound part of the question.should it be if 1=exp(2ikpi) then 1^x= exp(2ikpix) then consider the rational and irrational case on this form. but what's the differences , i have no idea
 
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cummings12332 said:
should it be if 1=exp(2ikpi) then 1^x= exp(2ikpix) then consider the rational and irrational case on this form.
Yes. Think about whether different values for k can produce the same value.
 
haruspex said:
Yes. Think about whether different values for k can produce the same value.

if rational, then 1^(p/q) is the q complex roots of 1, if x is irrational then 1^x=exp(2ikpix) then k can be chosen infinitely many values then there are infinite points
 
cummings12332 said:
if rational, then 1^(p/q) is the q complex roots of 1, if x is irrational then 1^x=exp(2ikpix) then k can be chosen infinitely many values then there are infinite points
That's it.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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