SOLUTION: Find the exact value of cos[arctan(pi/4)]

Question 888996: Find the exact value of cos[arctan(pi/4)]
Answer by Theo(13342) (Show Source): You can put this solution on YOUR website!
from what I can see about this, your solution would be as follows:

tan(x) = pi/4
since tan(x) = opposite side / adjacent side, this means opposite side is equal to pi and adjacent side is equal to 4.
hypotenuse is equal to sqrt(os^2 + as^2)
os = opposite side
as = adjacent side
h = hyhpotenuse
pythagorean formula is:
h^2 = os^2 + as^2 which becomes:
h^2 = pi^2 + 4^2 which becomes:
h^2 = pi^2 + 16
take the square root of both sides of this equation to get:
h = sqrt(pi^2 + 16)
that's your answer as far as i can see.

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