Question

2cos^2Beta-Cosbeta=0 (find all solutions for the equation in the interval 0, 2 pi). I have no idea how to go about doing this. Do you isolate the beta on one side? Would you be able to show me how and I'll solve for you to check?

Answer 1

cos B (2 cos B - 1 )=0
cos B = 0 is one solution. That is at pi/2 and 3pi/2
cos B = 1/2 is also a solution
that is at 60 degrees and -60 degrees which is at pi/3 and 5 pi/3

Answer 2

I thought cos=1/2 at 30, not 60