SOLUTION: Without using the calculator find 1/(sqrt(3)-tan (20°))+1/(sqrt(3)+tan(40°))+1/(sqrt(3)-tan(80°))

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Question 1143527: Without using the calculator find
1/(sqrt(3)-tan (20°))+1/(sqrt(3)+tan(40°))+1/(sqrt(3)-tan(80°))

Found 2 solutions by AnlytcPhil, Alan3354:
Answer by AnlytcPhil(1806) About Me  (Show Source):
You can put this solution on YOUR website!
This problem is very difficult.  I will only get it in terms of sin(20°).
Then it will involve the solving the cubic equation for sin(3q), which can be done, although it's a pain in the butt.


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Simplifying by multiplying each fraction by the LCD of each denominator:
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Change all the cos(60°)'s to 1/2 and
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Simplify by multiplying each numerator and denominator by 2, and sin(-20°) to -sin(20°)
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Get all the denominators to 4sin(20°) so we can combine the numerators 
over the common denominator:

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%281%5E%22%22%2B12sin%5E2%2820%5Eo%29-16sin%5E4%2820%5Eo%29%29%2F4sin%2820%5Eo%29%22%22=%22%22

20° is not a special angle; however, 60° is, and 60° = 3∙20°.

So look up the formula for sin(3q) and solve for sin(q) 


Edwin

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
That's a LOT of work.
And for what?
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As I posted earlier, the "answer" is the sin(60) or cos(30) --- using a calculator.
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What are you supposed to learn from this?