WhiteningProving de Moivre's Formula for Complex Numbers?

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Homework Help Overview

The discussion revolves around proving de Moivre's formula in the context of complex numbers, as presented in a homework question. The original poster expresses confusion regarding the problem's relevance to their coursework in mathematical physics, noting a lack of prior exposure to complex variables.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • The original poster attempts to connect their understanding of geometric series and Taylor expansions to de Moivre's formula, questioning the appropriateness of the problem given their background. Some participants suggest verifying the form of de Moivre's formula against the provided summands.

Discussion Status

The discussion is ongoing, with participants providing guidance on how to approach the problem. There is a suggestion to clarify the problem statement by posting it in text form rather than as an image, indicating a focus on improving communication for better assistance.

Contextual Notes

The original poster mentions that their class has not covered complex variables, which raises questions about the assumptions underlying the homework assignment. There is also a note about the preferred method of problem presentation within the forum.

Vitani11
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Homework Statement


Picture has been uploaded with question.

Homework Equations

The Attempt at a Solution



I have literally never seen anything like this in my life. I'm in mathematical physics. I looked up de Moivre's formula and I guess this comes from a course in complex variables? I don't know why this is a homework question given that nobody in my class has actually taken it, but whatever. I need to be able to prove this. Can you please help me out, where should I start? I am familiar with geometric series and I guess I can reference De Moivre's formula. That's where I'm at. My initial thought was that this had something to do with a taylor expansion, but I know cos(x)'s taylor expansion and I don't think that has anything to do with this.
 

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Write out de Moivre's formula and see if it has the same form as one of the summands you're given.
 
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Vitani11 said:
Can you please help me out, where should I start?
Start by posting an image that is right side up.
 
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LCKurtz said:
Start by posting an image that is right side up.

Better still: do not post an image at all; type out the problem (the much preferred PF way).
 
Okay.
 
Got it, thank you Teeth
 

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