SOLUTION: I have to find the exact value for this trigonometric expression. Help? :( cos (sin^-1 (1/4)) = ??

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Question 1030473: I have to find the exact value for this trigonometric expression. Help? :(
cos (sin^-1 (1/4)) = ??
Answer by fractalier(6550) About Me  (Show Source):
You can put this solution on YOUR website!
Draw a triangle such that the sine of an angle is 1/4. Then the adjacent side is sqrt(16-1) = sqrt(15).
The cosine of that same angle is sqrt(15)/4.