Complex Numbers Equation with Real Solutions

atarr3
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Homework Statement



Find real numbers p and q such that the following equation is true:

\frac{p}{q+5i}=4e^{\frac{-i\pi}{4}}

Homework Equations



Euler's formula

The Attempt at a Solution



Ok so I converted the right side to rectangular form using Euler's formula and solved for p. But I don't really know what do after that.

I got p=5\sqrt{2}q+25\sqrt{2}+25i\sqrt{2}-5qi\sqrt{2} but I don't know how to simplify this any further.
 
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Maybe p is equal to the real part of the right side and the imaginary part must equal zero. Which would make q=5 and p=50\sqrt{2}?
 
atarr3 said:
Maybe p is equal to the real part of the right side and the imaginary part must equal zero. Which would make q=5 and p=50\sqrt{2}?
Yep, that'll do it.
 
Haha ok thank you. I guess I didn't need to post this after all.
 
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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