Complex Numbers (1 Viewer)

[Vision]

Hey,

Simplify, leaving your answers in exact values.



Thanks in advance

 

[Carrotsticks]

Split cos(pi/7) as cos(2*pi/14) and use the appropriate double angle formula to eliminate the '1'.

Same for the sine, and it reduces to cis(something)/cis(something), which can be evaluated easily.

 

[anomalousdecay]

I remember doing this question exactly one year ago in Terry Lee's book I think. If I find my solution then I will post it up.

 

[Vision]

I remember doing this question exactly one year ago in Terry Lee's book I think. If I find my solution then I will post it up.

Haha yeah it was from Terry Lee. Don't worry about posing the solution though, I managed to figure it out (Thanks carrot).

 

[Drongoski]

Hope that's correct.

Edit: have used following identities:

 

[timeflies]

Wait... how did you get to there from the question? I'm a little lost :/

 

[rumbleroar]

Wait... how did you get to there from the question? I'm a little lost :/

You use double angle formula. I'll post up a picture.

 

[rumbleroar]

Let me know if it makes sense/doesn't make sense!

Apologies for off handwriting, hand is dead from MX1 study haha


Sent from my iPhone using Tapatalk

 

[timeflies]

View attachment 29342

Let me know if it makes sense/doesn't make sense!

Apologies for off handwriting, hand is dead from MX1 study haha


Sent from my iPhone using Tapatalk

Ohh I get it now! Thanks a lot