SOLUTION: Please help Given that the exact value of cos pi/5 = 1 + sqrt5/4, for each question calculate the exact value of the given expression. You may leave nested radicals in your answe

Algebra ->  Trigonometry-basics -> SOLUTION: Please help Given that the exact value of cos pi/5 = 1 + sqrt5/4, for each question calculate the exact value of the given expression. You may leave nested radicals in your answe      Log On


   



Question 1115434: Please help
Given that the exact value of cos pi/5 = 1 + sqrt5/4, for each question calculate the exact value of the given expression. You may leave nested radicals in your answer.
18. Cos 2pi/5
19. Cos pi/10

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Given that the exact value of cos pi/5 = 1 + sqrt5/4, for each question calculate the exact value of the given expression. You may leave nested radicals in your answer.
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cos+pi%2F5+=+1+%2B+sqrt5%2F4
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Makes no sense.