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**otownsend** Alright so by computing 1/3arccos(1/2), I get pi/9. This would be my first angle.

How would I calculate the second angle that is also between 0 and 2pi? I know that the second angle would be in quadrant 4, but I'm sure entirely sure how to find that angle. I tried subtracting pi/9 from 2pi, and I didn't get the correct answer.

I also tried finding the solutions between 0 and 2pi for the equation cos(pi/6)t=-2/3.5. I calculated pi/6arccos(2/3.5) to the value of t, and then I got the first solution by subtracting t from pi and then got the second solution by adding pi to t. Do you see where I went wrong in these steps?