Most of the are difficult to find.
For example . One can use this to get .
Thus, is the solution to the depressed cubic ....I did something like this somewhere, hold on....ah! look here. That'll give you a taste of what solving them is like.
I'm trying to find exact trigonometric values. Say I have sin11, I would use the special ratios:
and I would arrive with a surd answer, which is fine.
But I'm having trouble with angles like 20 and 40. Is there a reason for this?
Most of the are difficult to find.
For example . One can use this to get .
Thus, is the solution to the depressed cubic ....I did something like this somewhere, hold on....ah! look here. That'll give you a taste of what solving them is like.
Don't know if u can - at least not easily - found these links: Trigonometry Angles--Pi/18 -- from Wolfram MathWorld
http://mathworld.wolfram.com/TrigonometryAnglesPi9.html