SOLUTION: find all solutions for cos 3x = -1/2 when 0< x <2pi

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Question 1006712: find all solutions for cos 3x = -1/2 when 0< x <2pi
Answer by fractalier(6550) About Me  (Show Source):
You can put this solution on YOUR website!
cos 3x = -1/2
3x = cos(-1) (-1/2)
3x = 2(pi)/3 or 3x = 4(pi)/3
x = 2(pi)/9 or x = 4(pi)/9