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#1 2007-11-15 05:47:12
- tony123
- Member
- Registered: 2007-08-03
- Posts: 229
Evaluate
Evaluate cot x, given that
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#2 2007-11-15 06:41:52
- bossk171
- Member
- Registered: 2007-07-16
- Posts: 305
Re: Evaluate
The question could just as easily be evaluate sinx seeing how
cotx = sinx
multiply both sides sinx
cosx = sin²x
Using the trig identity sin²x + cos²x = 1 we get:
cosx = 1 - cos²x
u = cosx
u² + u - 1 = 0
u = (-1±√5)/2
cosx = (-1±√5)/2 = sin²x
sinx = cotx = √[(-1±√5)/2]
It's been a while since I had to do trig, did I make any mistakes?
There are 10 types of people in the world, those who understand binary, those who don't, and those who can use induction.
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