Complex Numbers! (1 Viewer)

harshsyd

New Member
Joined
Mar 8, 2017
Messages
4
Location
Sydney
Gender
Male
HSC
2018
Hey, I got two questions;

I'll attach the images as I cannot use LaTeX for some reason.

1. https://imgur.com/a/CFbQErW (I tried expanding and simplifying using bionomial, I do get correct answers but of course they are not in the forms of cot and so on, I get straight square roots, expected).

2. https://imgur.com/a/eF2Su32 (The only real place I am struggling is the last part, deducing the cos(2O) statement, rest is completed).

Thank You! :)
 

harshsyd

New Member
Joined
Mar 8, 2017
Messages
4
Location
Sydney
Gender
Male
HSC
2018
Thank you buddy, that was very nicely explained!
Except, how was the second last line derived? I understood up till 1+cosO+isinO/1-cosO-isinO...the half angles one, I am slightly lost
 
Last edited:

fan96

617 pages
Joined
May 25, 2017
Messages
543
Location
NSW
Gender
Male
HSC
2018
Uni Grad
2024




I think the start of that second last line you were talking about should read:

 

fan96

617 pages
Joined
May 25, 2017
Messages
543
Location
NSW
Gender
Male
HSC
2018
Uni Grad
2024
For your second question:

Let .



Note:


Similarly,


Going back to the original identity: multiplying the expression on the RHS and taking the real part of both sides,



And a few more lines of working give the required identity.
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top