[Complex Numbers] Ex 3E Q15) | [Solved] (1 Viewer)

A1La5

Member

Hi everyone.

I am struggling with part B of this question. Part A and C are straightforward but for Part B I have no idea how to relate the given substitution to the information in the question. I'm sure there's something really obvious that I'm missing but I can't see the connection.

The answer to part A is:

Last edited:

vishnay

Active Member
View attachment 31337

Hi everyone.

I am struggling with part B of this question. Part A and C are straightforward but for Part B I have no idea how to relate the given substitution to the information in the question. I'm sure there's something really obvious that I'm missing but I can't see the connection.

The answer to part A is:
View attachment 31338
Use de Moivre then equate imaginary

A1La5

Member
Alright, using the advice given I've gotten the sin(1/2@) in the denominator. After playing around for 30 minutes with the question I've managed to show everything except the sin(1/2n@) in the numerator. Where does the sin(1/2n@) come from..

idkkdi

Well-Known Member
Alright, using the advice given I've gotten the sin(1/2@) in the denominator. After playing around for 30 minutes with the question I've managed to show everything except the sin(1/2n@) in the numerator. Where does the sin(1/2n@) come from..
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