SOLUTION: evaluate with no calculator. sin[arccos(-2/3)]

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Question 334526: evaluate with no calculator. sin[arccos(-2/3)]
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
evaluate with no calculator. sin[arccos(-2/3)]
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cos[arccos(-2/3)] = -2/3
sin = sqrt(1 - cos^2) = sqrt(1 - 4/9)
sin = sqrt(5/9) = sqrt(5)/3