Question 1108591
Find all solutions of the equation in the interval [0,2π)

3 cot^2 x-9 = 0
cot^2(x) = 3
tan^2(x) = 1/3
tan(x) = +sqrt(3)/3
x = pi/6, 7pi/6
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tan(x) = -sqrt(3)/3
x = 5pi/6, 11pi/6